Question

What is the completely factored form of x3 + 4x2 – 9x – 36?

Answer 1

x^3 + 4x^2 – 9x – 36
= (x^3 - 9x) + (4x^2 - 36)
= x(x^2 - 9) + 4(x^2 -9)
= (x + 4) (x^2 - 9)
= (x + 4) (x - 3) (x + 3)

Done!

Answer 2

Answer:sdfsdfsdf

`(x+3)(x-3)(x+4)`

Explanation:

`x^3 + 4x^2- 9x - 36`

We factor this by grouping method, we group first two terms and last two terms,

`(x^3 + 4x^2)+(-9x - 36)`

Now take out GCF from each group

`x^2(x+4)+-9(x+4)`

Now factor out x+4

`(x^2-9)(x+4)`

Now factor x^2-3^2 using a^2-b^2 formula

`a^2-b^2=(a+b)(a-b)`

`x^2-3^2=(x+3)(x-3)`

`(x+3)(x-3)(x+4)`