Solve the equation using square roots. x^2 - 9 = 0

First, we need to get the X variable by itself.  To do this, we need to add 9 to both sides.

X^2 - 9 = 0

X^2 - 9 + 9 = 0 + 9

X^2 = 9

Now, we need to take the square root of both sides.

√(X^2) = √9

The square root of any squared number is the number itself.  Thus:

√(X^2) = +/-√9

X = +/-√9

X = +/-3

Thus:

X = 3 and X = -3