Question

Factor completely.
5x^2 + 10x - 40

Answer 1

Answer:

5(x + 4)(x - 2)

Step-by-step explanation:

Start by factoring 5 out of all three terms.  We then have

5(x^2 + 2x - 8), or

5(x^2 + 2x - 8), which is in proper quadratic form.

Note that (4)(-2) = 8 and that 4 - 2 = 2, which match the 3rd and 2nd coefficients of x^2 + 2x - 8.

Thus, in completely factored form, we have 5(x + 4)(x - 2)

Answer 2

Answer:

5 (x -2) (x +4)

Step-by-step explanation:

5x^2 + 10x - 40

Factor out a 5

5(x^2 +2x-8)

We can then factor inside the parentheses

What two numbers multiply to -8 and add to 2

-2*4 = -8

-2+4 = 8

5 (x -2) (x +4)