Question

Factor: x2 + 2x - 15

(x - 2)(x - 9)


(x - 3)(x + 5)


(x - 3)(x - 5)


prime

Answer 1

the trick is to find 2 numbers with a product equal to the last term and a sum equal to the coefficient of the middle term

Answer 2

x2 + 2x - 15 = x2 + 5x -3x -15
= x(x+5)-3(x+5)
= (x+5)(x-3)