Answer:
x = -3 or x = 3
Step-by-step explanation:
Subtract 9 from both sides.
x^2 - 9 = 0
Factor the left side. There is no common factor of the terms. It is a binomial which is the difference of two squares, so it factors into the product of a sum and a difference.
(x + 3)(x - 3) = 0
Set each factor equal to zero.
x + 3 = 0 or x - 3 = 0
Solve each equation.
x = -3 or x = 3
