6430.72=3.14r^2

Solution for 6430.72=3.14r^2 equation:

Simplifying
6430.72 = 3.14r2

Solving
6430.72 = 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.
6430.72 + -3.14r2 = 3.14r2 + -3.14r2

Combine like terms: 3.14r2 + -3.14r2 = 0.00
6430.72 + -3.14r2 = 0.00

Add '-6430.72' to each side of the equation.
6430.72 + -6430.72 + -3.14r2 = 0.00 + -6430.72

Combine like terms: 6430.72 + -6430.72 = 0.00
0.00 + -3.14r2 = 0.00 + -6430.72
-3.14r2 = 0.00 + -6430.72

Combine like terms: 0.00 + -6430.72 = -6430.72
-3.14r2 = -6430.72

Divide each side by '-3.14'.
r2 = 2048

Simplifying
r2 = 2048

Take the square root of each side:
r = {-45.254833996, 45.254833996}