Question

What are the factors of x2 − 9x − 10?

Answer 1

Using quadratic trinomials usi

Steps in factoring x^2 - bx - c, c is negative

Factor x^2 - 9x - 10

Step 1: Find the two integers whose product is -10 and whose sum is -9

-10 x 1 = -10 -10 + 1 = -9

Step 2: Use -10 and -1 to complete the factors.

x^2 - 9x - 10 = (x + 1)(x - 10)

Step 3: Use foil method to check the factors.

(x + 1)(x - 10) = x^2 - 10x + 1x - 10

= x^2 - 9x - 10

Thus, x^2 - 9x - 10 = (x + 1)(x - 10)

Answer 2

Explanation:

`{x}^(2) - 9x - 10 = 0 \\ {x}^(2) + x - 10x - 10 = 0 \\ x(x + 1) - 10(x + 1) = 0 \\ (x + 1)(x - 10) = 0 \\ x = - 1 \\ x = 10`