Question

CSecond chance! Review your workings and see you can correct your mistake. Fill in the gaps to factorise this expression. x^(2)+2x-15=(x-?)(x+?)

Answer 1

(x - 3)(x + 5)

Explanation:

x² + 2x - 15

consider the factors of the constant term (- 15) which sum to give the coefficient of the x- term (+ 2)

the factors are - 3 and + 5 , since

- 3 × + 5 = - 15 and - 3 + 5 = + 2 , then

x² + 2x - 15

= (x - 3)(x + 5) ← in factored form