### Home > A2C > Chapter Ch11 > Lesson 11.3.2 > Problem 11-149

11-149.

Square each side.

Set the equation equal to zero

Factor the equation.

*x* + 20 = *x*^{2}

0 = *x*^{2} − *x* − 20

*x* = 5

Here is the start of the process.

Complete the rest and check all possible answers.

*x* = 3 *x* = 11