Question

What are th factors of the expression below? -x +2x + 35

A. (x-5)(x-7) B. -1(x+5)(x-7) C. (x+5)(x-7) D. -1(x-5)(x+7)

Answer 1

option B

Explanation:

hope you meant - x²

You've choose factors of 35 which when added gives -2 and product gives -35. So i choose -7 and 5

`-x^2 + 2 x + 35 = -1 (x^2 - 2x - 35)`

`=-1 (x^2 - 7x + 5 x - 35)\\= -1 ( \ x(x - 7) + 5 (x - 7) \ )\\= - 1 (x+5)(x-7)`