#Factoring Help

112 messages · Page 1 of 1 (latest)

stoic trout
iron flax
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so for the first one

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what are you stuck with

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top left

stoic trout
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I've never been shown an example of this expression with a fraction before

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would it technically just be 4 or -4? I'm not sure

iron flax
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wdym

stoic trout
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I'm not sure, like the reciprocal of it or something but I'm just not sure how to use a fraction in this situation

iron flax
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well if x^2 = 1/4 what is x

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not considering the negative value

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btw the top right one you selected is right

stoic trout
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honestly I'm not sure how to get that

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and cool bet

iron flax
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try the different values you see for the coefficient of x

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is 1/2 * 1/2 = 1/4

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is 1/4 * 1/4 = 1/4

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since 64 is a square we can be pretty sure to factor it like that

stoic trout
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1/2*1/2 = 1/4
can I show u the work I have so far for it aswell?

iron flax
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ok

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so we have

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(1/2x+b)^2

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we know b = -8 or 8

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since b^2 = 64

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but since 2ab is negative

stoic trout
iron flax
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which one is it?

stoic trout
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I have m and n I think

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then I'd write it like this?

iron flax
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well we have 2ab = -8

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if we know a = 1/2

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what is b

stoic trout
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-16 = b

iron flax
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2 * 1/2 = 1

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1*b = -8

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then just write it in the form

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(a+b)^2

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and see which answer that matches

stoic trout
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ohhhhhh this is different, I was doing a different format
oops
let me try that

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the top answer?

iron flax
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yes

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now bottom left

stoic trout
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cool ty

iron flax
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what multiplies to ac adds to b

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so ac = 90 and b = -19

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so try to find the values

stoic trout
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so am I trying to find the gcf? and turn this equation into two binomials?

iron flax
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well 9 can be made in two ways

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9 * 1 and 3 * 3

stoic trout
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I'm not sure what two numbers can multiply and get to 90 and add to get to -19

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cuz I'm trying to find m+n and m*n, no?

iron flax
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try -9

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-9 * what = 90

stoic trout
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-10

iron flax
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ok

stoic trout
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OHHHH

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it works it works

iron flax
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ok

stoic trout
iron flax
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since the 10 and 9 add together we want them together

stoic trout
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I'm gonna switch the 9 and 10

iron flax
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since if they are seperate then will multiply

stoic trout
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there's no number besides one that can go into 9 and 10 hmm

iron flax
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assuming the non x values are negative

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if -10 * something = 10

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what is that something

stoic trout
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1

iron flax
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mb

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positive 10

stoic trout
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-1

iron flax
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ok and 9x * what = 9x^2

stoic trout
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ummm

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hm

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just, x?

iron flax
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yea

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so we have a 9x,x,-10,-1

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there is only one with those numbers

stoic trout
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so I would just multiply them by one?

iron flax
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which factored form has all those numbers as coefficients

stoic trout
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or 1x

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(9x-10)(x-1)

iron flax
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yes

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for the next one ac = 3 and b = 4

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basically the roots multiply to 3 and add to 4

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so what are they?

stoic trout
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I'm lost 😭 sorry, I'll figure this out eventually

iron flax
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well

stoic trout
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I think it's the bottom answer

iron flax
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there is only two integers that multiply to 3

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no

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what are they

stoic trout
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1 and 3

iron flax
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ok

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and since x = 1

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1 * 1 = 1

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so coeffcients of x,x,1,3

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which one is it?

stoic trout
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(x+3)(x+1)

iron flax
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yes

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now for the last

stoic trout
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last one is rhe same thing huh

iron flax
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basically

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since c is positive and b is negative

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we can assume both numbers we are looking for are negative

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so the 2 numbers multipled = 4

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and they are both negative

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there are only 2 integer sets for this

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can you list them?

stoic trout
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(x-4)(x-1)

iron flax
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yea

stoic trout
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or x,4,x,-1

stoic trout
# iron flax yea

cool ty!
thanks for being patient with me I appreciate your help

iron flax
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np