Which is a solution to (x - 2) (x + 10) = 13?

x = 3

x = 8

x = 10

x = 11

1. expand the equation

x^2 + 10x - 2x - 20 = 13

2. Collect like terms

x^2 + 8x - 20 = 13

3. Simplify

x^2 + 8x = 13 + 20

x^2 + 8x = 33

x^2 = 33 - 8x

4. Substitute answers for guess and check

3^2 = 33 - (8 x 3)

9 = 33 - 24

This equation is correct therefore x = 3