How do you factor by grouping $x^3 - 8x^2 - 7x + 56$ ?

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Answer 1 · 2018-06-28T23:00:07

$(x^2-7)(x-8)$

We have the following:

$color(lime)(x^3-8x^2)color(purple)(-7x+56)$

We can factor an $x^2$ out of the green terms, and a $-7$ out of the purple terms. Doing this, we get

$color(lime)(x^2)color(blue)((x-8))color(purple)(-7)color(blue)((x-8))$

Both terms have a $x-8$ in common, so we can factor that out to get

$(x^2-7)(x-8)$

Hope this helps!

How do you factor by grouping x^3 - 8x^2 - 7x + 56x^3 - 8x^2 - 7x + 56?