64-9r^2=0

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

Simplifying
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}