Question

An x-method chart shows the product a c at the top of x and b at the bottom of x. Above the chart is the expression a x squared + b x + c. If x – 10 is a factor of x2 – 8x – 20, what is the other factor? x +

Answer 1

(x-12) and (x+12)

Explanation:

Answer 2

The other factor is (x + 2).

Explanation:

If x - 10 is a factor of x^2 - 8x - 20 then we must find another factor that includes +2x, so that we have -10x + 2x = -8x. That factor is (x + 2):

x^2 - 8x - 20 = (x - 10)(x + 2)

As a test, multiply -10 and +2. We get -20, matching the constant of the given polynomial. Also, -10x + 2x = -8x, another match.