8x^2-72=0

Solution for 8x^2-72=0 equation:

Simplifying
8x2 + -72 = 0

Reorder the terms:
-72 + 8x2 = 0

Solving
-72 + 8x2 = 0

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '72' to each side of the equation.
-72 + 72 + 8x2 = 0 + 72

Combine like terms: -72 + 72 = 0
0 + 8x2 = 0 + 72
8x2 = 0 + 72

Combine like terms: 0 + 72 = 72
8x2 = 72

Divide each side by '8'.
x2 = 9

Simplifying
x2 = 9

Take the square root of each side:
x = {-3, 3}