Question

3) which expression is equivalent to 3x² - 10x - 8?A) (x - 4)(3x + 2) B) (3x - 4)(x - 2)C) (3x - 4)(x + 2)D) (3x -2)(x - 4)

Answer 1

We must find which expression is equivalent to the polynomial:

$3x^2-10x-8.^{}$

To answer this, we compute the products of the different monomials.

A)

$(x-4)\mleft(3x+2\mright)=3x^2+2x-12x-8=3x^2-10x-8\text{ }✓$

B)

$\mleft(3x-4\mright)\mleft(x-2\mright)=3x^2-6x-4x+8=3x^2-10x+8\text{ }✖$

C)

$(3x-4)\mleft(x+2\mright)=3x^2+6x-4x-8=3x^2+2x-8\text{ }✖$

D)

$(3x-2)\mleft(x-4\mright)=3x^2-12x-2x+8=3x^2-14x+8\text{ }✖$

Answer

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