Question

Use the grouping method to factor 5x3 + 15x2 – 2x – 6.

A. (x – 2)(5x2 + 3)
B. 5x(x + 1)(x – 6)
C. (x + 3)(5x2 – 2)
D. (x – 3)(5x2 + 2)

Answer 1

The answer is

C. (x+3)(5x2-2)

Answer 2

`(x+3)(5x^2-2)`

C is the correct option.

Explanation:

The given expression is
`5x^3+15x^2-2x-6`

Make groups as shown below to factor

`(5x^3+15x^2)+(-2x-6)`

Now, factored out the GCF from each group

`5x^2(x+3)-2(x+3)`

Factored out the common term (x+3)

`(x+3)(5x^2-2)`

Therefore, the factored form is
`(x+3)(5x^2-2)`

C is the correct option.