Question

Factor this polynomial expression.

15x^2- 2x - 8
O A. (5x + 4)(3x - 2)
O B. (5x - 4)(3x+2)
O C. (5x + 2)(3x - 4)
O D. (5x-2)(3x+4)

Answer 1

B. (5x - 4)(3x + 2)

Explanation:

Factor the following:

`\longrightarrow` 15x² - 2x - 8

The coefficient of x² is 15 and the constant term is -8. The product of 15 and -8 is -120. The factors of -120 which sum to -2 are 10 and -12.

So,

`\longrightarrow` 15x² + (10 - 12)x - 8

`\longrightarrow` 15x² + 10x - 12x - 8

`\longrightarrow` 5x(3x + 2) - 4(3x + 2)

`\longrightarrow` (5x - 4)(3x + 2)