Question

Find the zeroes of the polynomial using the quadratic formula.

2x2 − 3x − 15 = 5

11

−5/2

5

4

Answer 1

Explanation:

2x² - 3x - 15 = 5

2x² - 3x - 20 = 0

Quadratic formula

x = [3 ± √(3² – 4·2(-20))] / [2·2]

 = [3 ± √169] / 4

 = [3 ± 13] /4

 = -2.5, 4