Question

Which inequality below satisfies the solution set graphed on the following number line?

Answer 1

D.

Explanation:

The function must have the range -3 to 5.

2x^2 - 4x - 30

= 2(x^2 - 2x - 15)

= 2(x + 3)(x - 5)

so the critical points are -3 and 5.

When x = -2 f(x) = 2* 1 * -7 = -14 <= 0

when x = 4 f(x) = 2 * 7 * -1 <= 0.

when x= 0 f(x) < 0

So its the last option.