Question

Determine the factors of 3x^2 + 10x − 8.

(3x − 8)(x + 1)
(3x − 1)(x + 8)
(3x − 4)(x + 2)
(3x − 2)(x + 4)

Answer 1

(3x - 2)(x + 4).

Explanation:

3x^2 + 10x − 8

3 + -8 = -24.

We need 2 numbers whose product is -24 and whose sum is + 10.

They are -2 and 12, so we write:

3x^2 + 12x - 2x - 8

= 3x(x + 4) - 2(x + 4)

= (3x - 2)(x + 4).

Answer 2

Option 4

Explanation:

3x² + 10x - 8 = 3x² + 12x - 2x - 2*4

= 3x(x +4) - 2(x + 4)

= (x + 4)(3x - 2)