Answer:
x^3 + 4x^2 - 7x - 10
Step-by-step explanation:
To solve this we're going to use Polynomial multiplication, starting by multiplying (x-2)(x+1) = x^2 - 2x + x - 2 = x^2 - x - 2. Next, we will multiply (x^2 - x - 2)(x+ 5) = x^3 + 5x^2 -x^2 - 5x -2x -10 = x^3 + 4x^2 - 7x - 10.
rearrange the equation to where you set it equal to 0 by moving the 25 over.
n2 - 8n -9 = 0
now factor
(n-9)(n+1)
so n1 = 9
n2 = -1