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brave crow Mar 2, 2023, 10:02 AM

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Dose anyone have any idea how to do this, i just keep on getting mixed up 🥲

snow flicker Mar 2, 2023, 10:08 AM

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Ok so they only want AB in terms of x so you don’t need to solve for x in part A
we see that AB comprises of 4cm and xcm, so add them up, and you get (x+4)cm

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In part B, they mean the area of the entire shape, we already have (x+4) cm as the length, but the width is AD, which is 6cm + xcm, so AD is (x+6)cm

snow flicker Mar 2, 2023, 10:09 AM

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brave crow Dose anyone have any idea how to do this, i just keep on getting mixed up 🥲

does this make sense?

brave crow Mar 2, 2023, 10:10 AM

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i did (X+4)(X+6)=28CM^2

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Then like tried solving it so x would be on it own

snow flicker Mar 2, 2023, 10:11 AM

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You don’t have to solve it, the question only wants you to rearrange this in the form x^2 + ax = b

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So all you need to do is expand the brackets, and take all the terms with no x coefficents to the right

snow flicker Mar 2, 2023, 10:12 AM

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brave crow i did (X+4)(X+6)=28CM^2

make sense? ^

brave crow Mar 2, 2023, 10:12 AM

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so like? x^2=....

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oh

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wait

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oh

snow flicker Mar 2, 2023, 10:13 AM

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so expand the brackets, you get
x^2 + 6x + 4x + 24 = 28
x^2 + 10x + 24 = 28
x^2 + 10x = 28 - 24
x^2 + 10x = 4

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Then you can get your a and b values

brave crow Mar 2, 2023, 10:14 AM

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whats the name of this system of woking out? ( i forgot 🥲 )

snow flicker Mar 2, 2023, 10:14 AM

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Expanding brackets mostly

brave crow Mar 2, 2023, 10:14 AM

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K

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oh

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so how did u see that u had to use expanding brackets to work it out?

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