196=3.14r^2

Solution for 196=3.14r^2 equation:

Simplifying
196 = 3.14r2

Solving
196 = 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.
196 + -3.14r2 = 3.14r2 + -3.14r2

Combine like terms: 3.14r2 + -3.14r2 = 0.00
196 + -3.14r2 = 0.00

Add '-196' to each side of the equation.
196 + -196 + -3.14r2 = 0.00 + -196

Combine like terms: 196 + -196 = 0
0 + -3.14r2 = 0.00 + -196
-3.14r2 = 0.00 + -196

Combine like terms: 0.00 + -196 = -196
-3.14r2 = -196

Divide each side by '-3.14'.
r2 = 62.42038217

Simplifying
r2 = 62.42038217

Take the square root of each side:
r = {-7.900657072, 7.900657072}