14,16,20,22,23 | Mathematics | Page 1

molten kestrel Oct 18, 2023, 11:24 PM

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gleaming wharfBOT Oct 18, 2023, 11:24 PM

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molten kestrel

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molten kestrel Oct 19, 2023, 12:49 AM

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.

molten kestrel Oct 19, 2023, 1:11 AM

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despair

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i been waiting 2 hrs

limpid osprey Oct 19, 2023, 1:30 AM

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wow you have a lot of quadratic questions

limpid osprey Oct 19, 2023, 1:30 AM

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molten kestrel i been waiting 2 hrs

ang progress in those 2hrs

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for 14 consider a and b as the side lenghts

molten kestrel Oct 19, 2023, 1:41 AM

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limpid osprey ang progress in those 2hrs

no

molten kestrel Oct 19, 2023, 1:42 AM

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limpid osprey for 14 consider a and b as the side lenghts

ok so 2a+2b=400

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and ab=8000

limpid osprey Oct 19, 2023, 1:42 AM

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yup

molten kestrel Oct 19, 2023, 1:42 AM

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what do i do from there

limpid osprey Oct 19, 2023, 1:43 AM

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well what does it look like

molten kestrel Oct 19, 2023, 1:43 AM

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no clue

limpid osprey Oct 19, 2023, 1:44 AM

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two variables...

molten kestrel Oct 19, 2023, 1:45 AM

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okay

molten kestrel Oct 19, 2023, 1:46 AM

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limpid osprey two variables...

what do i do

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with them

limpid osprey Oct 19, 2023, 1:47 AM

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two varaibles, two equations...

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ring any bells?

molten kestrel Oct 19, 2023, 1:47 AM

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not really

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oh

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a line

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2 lines

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what do i do with them

limpid osprey Oct 19, 2023, 1:49 AM

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systems of equations?

molten kestrel Oct 19, 2023, 1:50 AM

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whats that

limpid osprey Oct 19, 2023, 1:50 AM

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simutanious euqatoins

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it has weird names

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idk which one you might have heard

molten kestrel Oct 19, 2023, 1:50 AM

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idk what that is

molten kestrel Oct 19, 2023, 1:50 AM

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limpid osprey idk which one you might have heard

neither

limpid osprey Oct 19, 2023, 1:51 AM

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so like how would you solve x+y=2
x-y=0

molten kestrel Oct 19, 2023, 1:52 AM

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limpid osprey so like how would you solve x+y=2 x-y=0

y=-x+2

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oh

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okay i can make them a equation

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now i have y=-x+200 for the perimeter

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what do i do for the 2nd one

limpid osprey Oct 19, 2023, 1:55 AM

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substitute

molten kestrel Oct 19, 2023, 1:55 AM

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okay

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i got -x^2+200x-8000

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are the dimensions the vertex

limpid osprey Oct 19, 2023, 1:57 AM

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roots

molten kestrel Oct 19, 2023, 1:57 AM

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okay

molten kestrel Oct 19, 2023, 2:03 AM

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limpid osprey roots

i got 34.16 and 234.16 but the answer sheet says its 55.28 and 144.72

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limpid osprey Oct 19, 2023, 2:05 AM

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,w -x^2+200x-8000=0

sinful laurelBOT Oct 19, 2023, 2:05 AM

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limpid osprey Oct 19, 2023, 2:05 AM

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,w 20(5+sqrt(5))

sinful laurelBOT Oct 19, 2023, 2:05 AM

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Results provided by WolframAlpha

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molten kestrel Oct 19, 2023, 2:05 AM

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how u do that

limpid osprey Oct 19, 2023, 2:05 AM

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okay you have a calculation error somewhere

molten kestrel Oct 19, 2023, 2:06 AM

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k

molten kestrel Oct 19, 2023, 2:08 AM

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limpid osprey ,w -x^2+200x-8000=0

i got it can we do 16

limpid osprey Oct 19, 2023, 2:09 AM

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how does something get 2 zeroes

molten kestrel Oct 19, 2023, 2:09 AM

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b^2-4ac>0

limpid osprey Oct 19, 2023, 2:09 AM

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so what is b here

molten kestrel Oct 19, 2023, 2:10 AM

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limpid osprey so what is b here

-3+2k

limpid osprey Oct 19, 2023, 2:10 AM

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there you go

molten kestrel Oct 19, 2023, 2:10 AM

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what do u mean

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am i done already

limpid osprey Oct 19, 2023, 2:11 AM

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molten kestrel b^2-4ac>0

substitute here

molten kestrel Oct 19, 2023, 2:11 AM

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ok

molten kestrel Oct 19, 2023, 2:13 AM

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limpid osprey substitute here

4k^2-12k-7>0

limpid osprey Oct 19, 2023, 2:13 AM

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uhh show steps?

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also where did the > sign go

molten kestrel Oct 19, 2023, 2:14 AM

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should be c=1

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and b=-3+2k

limpid osprey Oct 19, 2023, 2:16 AM

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alr

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just remember your > sign

molten kestrel Oct 19, 2023, 2:17 AM

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limpid osprey just remember your > sign

for the zeros i got 7/2 and -1/2

limpid osprey Oct 19, 2023, 2:18 AM

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alright, now for the > sign

molten kestrel Oct 19, 2023, 2:22 AM

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what about it

limpid osprey Oct 19, 2023, 2:23 AM

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well it tells you your range

molten kestrel Oct 19, 2023, 2:24 AM

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limpid osprey alright, now for the > sign

how do i know whats 2 zeros and whats none

limpid osprey Oct 19, 2023, 2:25 AM

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molten kestrel b^2-4ac>0

remember this

molten kestrel Oct 19, 2023, 2:25 AM

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okay

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what numbers do i put for it

limpid osprey Oct 19, 2023, 2:26 AM

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molten kestrel

so this is b^2 4ac blah blah

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but this needs to be ABOVE 0

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so uh

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how would you solve this

molten kestrel Oct 19, 2023, 2:27 AM

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ok lemme try

molten kestrel Oct 19, 2023, 2:27 AM

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limpid osprey how would you solve this

idk

limpid osprey Oct 19, 2023, 2:28 AM

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okay remember a quadratic has two sections

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so the x values between the zeroes and the x values not between the zeroes are either pos or neg

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but not the same

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so just test a value of x

molten kestrel Oct 19, 2023, 2:28 AM

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okay

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got it

molten kestrel Oct 19, 2023, 2:30 AM

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limpid osprey so just test a value of x

now 20

limpid osprey Oct 19, 2023, 2:30 AM

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assume the middle is a y=0, now find three points that are on the parabola and get the equation ax^2+bx+c and solve for a b and c

molten kestrel Oct 19, 2023, 2:31 AM

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bet

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i got the wrong answer

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did i do smt wrong

limpid osprey Oct 19, 2023, 2:37 AM

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maybe it means at y=8 the two points are 6m apart

molten kestrel Oct 19, 2023, 2:38 AM

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i got the answer to 20a

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now 22

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almost done

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i had 23 questions assigned today

molten kestrel Oct 19, 2023, 3:00 AM

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limpid osprey maybe it means at y=8 the two points are 6m apart

how do i do 22?

limpid osprey Oct 19, 2023, 3:04 AM

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well when you see “will x hit y” what do you think about

molten kestrel Oct 19, 2023, 3:10 AM

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i got 23

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its just 22 now

molten kestrel Oct 19, 2023, 3:11 AM

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limpid osprey well when you see “will x hit y” what do you think about

the intersection

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+close

#14,16,20,22,23