Question

Which of the following is a factor of 2x^2–7x–15

2x–3
x–5
2x–5
x–3

Answer 1

double bracket factorisation

2 × 15 = 30

find two factors of 30 that add to give -7

(-10, +3)

2x^2 -10x + 3x - 15

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

(2x+3) (x-5)

THE ANSWER IS X-5