#maths hw

1 messages · Page 1 of 1 (latest)

sick yarrow
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U want explanation or answer

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can’t see much tbh

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But for the second one

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what’s the shape of the graph

visual peak
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take a clear image

sick yarrow
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Sure

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Send it here

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@agile plume

wise sentinel
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Centre (0,0) and radius of 2 so x^2+y^2=4

sick yarrow
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oof he done it

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Also @agile plume when u see $x^2 + y^2=4$ if u square root the 4, that means 2 is the radius

waxen stoneBOT
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i5h y9 -> y10

597909351562477568.png
sick yarrow
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…

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another example, if $x^2 + y^2=36$ is the equation of a circle, the square root of 36 is 6, so that would mean 6 is the radius

waxen stoneBOT
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i5h y9 -> y10

597909351562477568.png
sick yarrow
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yea

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and say for example if it’s something like $(x+7)^2 + (y-4)^2$ by flipping the numbers in the bracket, we find out that -7,4 are the coordinates of the circle

waxen stoneBOT
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i5h y9 -> y10

597909351562477568.png
sick yarrow
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so overall, by flipping the numbers in the bracket, u can find the coordinates of the circle, and by square rooting the number after the = gives u the radius

open herald
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Estimate radius as 40cm and height as 100cm and π as 3

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Volume of a cylinder = πr²h

sick yarrow
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Use the formula

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so $pi multiplied by 40^2 multiplied by 100$

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Oml

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$pi$

waxen stoneBOT
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i5h y9 -> y10

597909351562477568.png
sick yarrow
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$3.14x40^2x100$

waxen stoneBOT
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i5h y9 -> y10

597909351562477568.png
sick yarrow
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no wait

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the bot isn’t working

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But yes what u said is right

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No wait

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3pi x 40^2 x 100

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$3pi x 40^2 x 100$

sick yarrow
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yes

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1000cm^3=1 litre

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So convert your answer

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Foundation

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Higher this would prob be 2 marks lol

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Is it?

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Damn how is that 4

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@agile plume

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$3\pi * 40^2 *100$

waxen stoneBOT
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i5h y9 -> y10

597909351562477568.png
sick yarrow
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  • means multiply
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If u needed a visualisation

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Need anymore help?

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prob 9 or 10

open herald
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No use π≈3

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It will be a whole number

sick yarrow
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then divide your answe by 1000

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,w 3x40x100

waxen stoneBOT
sick yarrow
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So 12

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Since it asks for your answer to be in Litres

open herald
sick yarrow
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oh ye

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mb

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Np

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Sure

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@agile plume what’s the q

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I think area of the trapezium is 36

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Wait no

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56

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@violet dome how do u work out the first one

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I have a couple ideas but not completely sure

violet dome
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what

cedar sphinx
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3 pings tf

sick yarrow
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How do u work out this one

sick yarrow
violet dome
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well so

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square base

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so whats surface area of one box

rustic yarrow
sick yarrow
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@agile plume

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He asks for help then he’s gone 😶

rustic yarrow
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You could either work out the area separately so first the square then triangle

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Or use the 1/2(a+b)h eqn

rustic yarrow
sick yarrow
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Cl I haven’t done the first type of question ina. While

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U find the area of the block and times by 60?

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Or sa

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@rustic yarrow

rustic yarrow
sick yarrow
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@rustic yarrow

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I got no she isn’t

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Because she needs 200cm more

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sorry for the ping

rustic yarrow
rustic yarrow
sick yarrow
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yea so answer is no because needs 200cm more for first one

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And second one it’s 56cm

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but you really should ask for working

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otherwise you won’t benefit/learn

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ok first one

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5x5+5x5+2x5+2x5+5x2+5x2=90

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90x60=5400

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But she only has 5200

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So she needs 200cm more

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Therefore incorrect

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Second one

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10+4/2=7x8=56cm^2

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second one is for the area yes

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Idk if it’s right but 22

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Either 22 or 30

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Perimeter u just add all the sides

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acc idk

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ye but the answer might be wrong

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nw

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Need anymore help before I go

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I have like 15 mor mins

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so if u need any help tell now

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Which one

visual peak
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so first the first question

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its asking u for the area

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area of a circle = pi x r^2

sick yarrow
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Pir^2

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49pi

visual peak
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d = 2r
14 = 2(7)
so the radius is 7

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7^2 = 49 x pi

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49pi yes

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hmm#

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so its asking for the area of the shape

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the shape is a triangle and trapezium

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area of triangle + area of trapezium = total area

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ok do u know how to work out the area of a triangle

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um

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no

sick yarrow
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b x h/2

visual peak
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ok so it's 1/2 x base x height

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whats the base?

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ye

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yep

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not quite

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the base is literally the base

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the base is 100cm

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70 is the height

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(u can tell that as its vertical)

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its for both

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anyways

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1/2 x base x height

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1/2 x 100 x 70

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1/2 x 7000

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thats 3500cm^2

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no problem

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alright so for the trapezium

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the formula is

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((a + b) / 2) x h

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its better to do this:

(a + b) x h / 2

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not quite

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a and b are both the parallel sides

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the top and bottom

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here the trapezium is inverted (upside down)

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yep, just make sure u put 100 + 80 in brackets so that u can solve that first

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actually ur incorrect

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look here

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130cm is the total height of both the trapezium and the triangle

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70cm is only for the triangle

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ur finding the trapeziums height

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so u do 130 - 70 = 60cm

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great

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(100 + 80) x 60 / 2

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180 x 60 / 2
10800 / 2
5400 cm^2

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yes great

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ok lets go back to this statement

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total area = area of triangle + area of trapezium

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total area = 3500 + 5400
total area = 8900 cm^2

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hope that helps (check the mark scheme)

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yes

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area of the triangle = 3500
area of the trapezium = 5400
total area = A of triangle + A of trapezium
total area = 3500 + 5400
total area = 8900 cm^2

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ah ok

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yeah man no problem

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im going into y11

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its a 9

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even though i sometimes get 8s

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all subjects is 7+

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yep gcse re

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got a 6 😭

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i was getting 8s throughout

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i got like 145 and the grade boundary was 147 for a 7 i think

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aqa

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science im predicted 8s english 8s maths 9 cs 6

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i do history but idk my predicted

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talk to ur teacher about it

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oh

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i would say to revise a lot for ur end of years

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especially maths english and science

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just the core subjects

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yep u dont

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it depends on ur career

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but i think science as a core subject has its own importance

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theres a reason why its a core subject

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probably because sixth forms may be able to distinguish ur ability

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eh

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even though gcses dont really matter

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i would just focus on the main subjects

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lets say u want to do cs at uni

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focus in maths science and cs but also english or else u would have to resit

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what do u want to do at uni?

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yep

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oh alright

visual peak
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yep send

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go on

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ok this is something u have to memorise

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the first one is E

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pretty sure its a reciprocal graph

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second one is D

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the fourth one is A

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last one is B

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third one is C using trial and error - was not sure about it myself

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no problem

pine path
sick yarrow
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sure

vocal junco
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All you need to know is that

  • sin(180 - x) = sin(x)
  • cos(360 - x) = cos(x)
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Yes

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What's a value for which sin(x) = root3 / 2?

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sin^-1(root3/2)

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That's one answer

vocal junco
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No

hoary atlas
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The pings in this channel are gonna make me insane fr

vocal junco
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Real

hoary atlas
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Someone is @ ing maths mentor

vocal junco
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Sin^-1(root3/2) = 60 right

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So sin(60) = sin(180 - 60)

agile plume
vocal junco
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Yeah

sick yarrow
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Do u know the rules of congruence

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SSS ASA RHS and I think sas

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I’m prob wrong

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ok now using those congruence stuff show that they aren’t similar

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Are all the sides the same

sick yarrow
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So that means they aren’t similar

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Idk I cant really explain properly

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I’m prob wrong

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U should prob ask someone else tbh

hoary atlas
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You don’t need rules of congruence for this

sick yarrow
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Oh

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So it’s not similar because it has different angles?

hoary atlas
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You can just say internal angles not equal so not similar

sick yarrow
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Ah ok

modern wolf
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theyre similar as all angles are the same

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theres two alternate angles
QPR = RTS
PQR = RST
and then the opposite angles PRQ and SRT are the same

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so in those two triangles all the angles are the same but the lengths arent the exact same so, similar

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yep, im assuming you have to explain so talk about the alternate and opposite angles due to ST and PQ being parallel

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first you have to figure out which sides are proportionate to each other due to the angles

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and with that its SR and RQ are scale factors of each other so you divide it to figure out wht it is

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27/6 = 4.5 (so thats the scale factor of the smaller triangle to the bigger one

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so to find a, times 8 by 4.5 and you get 36
to find b, DIVIDE 22.5 by 4.5 and you get 5

a= 36
b= 5

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np 🙏

visual peak
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sure

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had some internet issues

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now im back

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hmm

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both?

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alright

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im thinking its reversed percentages

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um i may be wrong

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but we can ifnd out how many were in 2014

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and then just do 122% = x and then divide both sides by 122 and then multiply it again by 100 to get the original (100%)

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0.8 x 7076 = 5660.8

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u cant have .8 of a visistor so 5660

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hmm wait

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yeah ok

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lets say the missing value of 2014 is y

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so y x 0.8 = 7076
y = 7076/0.8
y = 8845 visitors

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y = 8845 visitors in 2014

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u following so far?

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alright so as this is 22% more of the previous year (2013)

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we can just do simple reverse percentages

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122% = 8845
1% = 72.5
100% = 7250

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so in 2013 there were 7250 visitors

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there may be a way easier method but this is just how i'd do it

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yep np

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alright for the second one

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its simple inverse proportion

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P = 1 / q^2

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3.4 = 1 / 25

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let 1 be k - a constant

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3.4 = k / 25

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3.4 x 25 = k

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k = 85

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so now u can write it as:

P = k / q^2

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find the value of P when q = 2

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so just pluggin in the values

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P = k / 2^2

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P = 85 / 4

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p = 21.25

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thats ur answer

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no problem

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its better to watch a video on these stuff tho

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it clears it up

thorny vigil
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alr

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for first one

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convert 120m into km

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then divide by 3600

sick yarrow
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For the second one rearrange the formula to make it pressure x volume = area

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Find the colume of the the rectangle and multiply by 48

rustic yarrow
thorny vigil
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oh ye

heady owl
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288N

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force = pressure x area

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48 x 6 = 288N

sick yarrow
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np

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I thought u could work it out

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but it’s alr

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oh

sick yarrow
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Sure

sick yarrow
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Yh

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Do u know error intervals

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hmmm

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well it’s correct to 1dp right

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so what value would u get 5.3 for if u rounded up to 1dp

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so let’s cal the value x

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x rounded to 1 dp is 5.3

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so what would the value of x be

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and the value of x would be your lower bound

spark reef
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so sin is o/h, and we know that the value of sin increases with the angle right ?

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look at the graph to convince urself (or look at triangles)

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So to find upper and lower bounds for the angle, we need to find upper and lower bounds for o/h

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The upper bound is found by: biggest O/smallest H

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And lower bound: smallest O/biggest H

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Then from that use sin functions to find upper and lower bounds for the angle

sick yarrow
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@agile plume

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do u understand

visual peak
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with whaT

sick yarrow
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is p 7

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because tan can be written as sin/cos

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and the 2 cos chancel out

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And u can rewrite the equation

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To give 7sinx

visual peak
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this isnt gcse

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are u doing gcse fm

granite hollow
earnest oxide
hoary atlas
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in

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sane

granite hollow
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Real

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Ez paper fr

sick yarrow
sick yarrow
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I think 8 is 0.4

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But I’ve never done this

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Ask @granite hollow

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since they are passively reacting

granite hollow
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I failed maths idk

sick yarrow
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ofc u did

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dk y I asked u

granite hollow
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Hey look there’s a mentor around

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@hoary atlas you wouldn’t mind helping would you?

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Why would I know the answer if I failed maths

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Why are you pinging me lad I’m right here

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I got a U both times

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Yes

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That’s where I should be

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Maths

hoary atlas
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Okay

granite hollow
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Every grade counts fr

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Damn

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Where’s the belief

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@hoary atlas 😡

hoary atlas
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what

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P(A U B) = P(A) + P(B)

granite hollow
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🔥

hoary atlas
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since P(A and B) = 0

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sad

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bro needs to learn PIE

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0.7-0.3

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cold

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how long is this thread

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holy cow

sick yarrow
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600 messages worth of hw

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how much did u get

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why u doing it then

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Cl tho have u reallt learn anything

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Since u just ask mentors for the answer

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Damn

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Needs to be 100 mate

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Got ur exams this year

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do u need anymore help

tulip jay
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YOOO FAZZZZZ

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THIS WAS MY THREADD

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OLD ACCOUNT GOT DELTEDD

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AND THEY NEVER DID CHECK FFS

granite hollow
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womp womp

tulip jay
granite hollow
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im not too good at maths

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at least clarence has your back

tulip jay
tulip jay
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i got a 5 instead

sick yarrow
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Also idk y but this thread was like showing

granite hollow
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its showing because people have recently messaged in it

granite hollow
tulip jay