Question

Factor completely 2x2 − 6x − 36.

Answer 1

2(x − 6)(x + 3)

Explanation:

First, we can factor out the greatest common factor, which is 2:

2(x^2 - 3x - 18)

Now we need to factor the quadratic expression inside the parentheses. We need to find two numbers whose product is -18 and whose sum is -3.

The two numbers are -6 and +3, since (-6)×(+3)=-18 and (-6)+(+3)=-3.

So we can write:

2(x − 6)(x + 3)