72.3455=3.14r^2

Solution for 72.3455=3.14r^2 equation:

Simplifying
72.3455 = 3.14r2

Solving
72.3455 = 3.14r2

Solving for variable 'r'.

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

Add '-3.14r2' to each side of the equation.
72.3455 + -3.14r2 = 3.14r2 + -3.14r2

Combine like terms: 3.14r2 + -3.14r2 = 0.00
72.3455 + -3.14r2 = 0.00

Add '-72.3455' to each side of the equation.
72.3455 + -72.3455 + -3.14r2 = 0.00 + -72.3455

Combine like terms: 72.3455 + -72.3455 = 0.0000
0.0000 + -3.14r2 = 0.00 + -72.3455
-3.14r2 = 0.00 + -72.3455

Combine like terms: 0.00 + -72.3455 = -72.3455
-3.14r2 = -72.3455

Divide each side by '-3.14'.
r2 = 23.03996815

Simplifying
r2 = 23.03996815

Take the square root of each side:
r = {-4.799996682, 4.799996682}