Solve for x. Express your answer in simplest radical form if necessary.
x^2 = 81
Taking the square root of both sides of the equation, we have:
x = ±√81
x = ±9
Therefore, x can be either 9 or -9.
x^2 = 81
x = ±√81
x = ±9
Therefore, x can be either 9 or -9.