9r^2-64=0

Solution for 9r^2-64=0 equation:

Simplifying
9r2 + -64 = 0

Reorder the terms:
-64 + 9r2 = 0

Solving
-64 + 9r2 = 0

Solving for variable 'r'.

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

Add '64' to each side of the equation.
-64 + 64 + 9r2 = 0 + 64

Combine like terms: -64 + 64 = 0
0 + 9r2 = 0 + 64
9r2 = 0 + 64

Combine like terms: 0 + 64 = 64
9r2 = 64

Divide each side by '9'.
r2 = 7.111111111

Simplifying
r2 = 7.111111111

Take the square root of each side:
r = {-2.666666667, 2.666666667}