4x^2-9=72

Solution for 4x^2-9=72 equation:

Simplifying
4x2 + -9 = 72

Reorder the terms:
-9 + 4x2 = 72

Solving
-9 + 4x2 = 72

Solving for variable 'x'.

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

Add '9' to each side of the equation.
-9 + 9 + 4x2 = 72 + 9

Combine like terms: -9 + 9 = 0
0 + 4x2 = 72 + 9
4x2 = 72 + 9

Combine like terms: 72 + 9 = 81
4x2 = 81

Divide each side by '4'.
x2 = 20.25

Simplifying
x2 = 20.25

Take the square root of each side:
x = {-4.5, 4.5}