Question

What are the x-intercepts of y = 2x2 - 3x - 20?

A) x = -5 and 2
B) x = 5 and -2
C) x = -2.5 and 4
D) x = 2.5 and -4

Answer 1

x-intercepts when y = 0
so

2x^2 - 3x - 20 = 0
(2x + 5)(x - 4) = 0

2x + 5 = 0
x = -5/2
x = -2.5

x - 4 = 0
x = 4

answer:

C) x = -2.5 and 4