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I dont understand how to do this
its factoring quadratics

I dont understand how to do this its factoring quadratics-example-1
User Supriya
by
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1 Answer

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olume = length * height * width

Therefore 280 = 4 * (n + 2) * (n + 5)

Divide both sides of the equation by 4

70 = (n + 2)(n +5)

Expand

70 = n^2 + 5n + 2n + 10

Subtract 70 from both sides and simplify

0 = n^2 + 7n -60

Factor

(n +12)(n -5) = 0

Therefore n = -12 or + 5

As n cannot be less than -2 as you cannot have a negative dimension, it means that n = 5 and the sides are 4, (5 + 2), (5 + 5) = 4, 7 and 10 inches respectively

Volume is therefore

4*7*10 = 280 = correct

Hope this helped!

User Rick Hanlon II
by
7.8k points
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