A(r)=3.14xr^2

Solution for A(r)=3.14xr^2 equation:

Simplifying
A(r) = 3.14xr2

Multiply A * r
rA = 3.14xr2

Solving
rA = 3.14r2x

Solving for variable 'r'.

Combine like terms: 3.14r2x + -3.14r2x = 0.00
rA + -3.14r2x = 0.00

Factor out the Greatest Common Factor (GCF), 'r'.
r(A + -3.14rx) = 0.00

Subproblem 1
Set the factor 'r' equal to zero and attempt to solve:

Simplifying
r = 0

Solving
r = 0

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

Simplifying
r = 0
Subproblem 2
Set the factor '(A + -3.14rx)' equal to zero and attempt to solve:

Simplifying
A + -3.14rx = 0

Solving
A + -3.14rx = 0

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

Add '-1A' to each side of the equation.
A + -1A + -3.14rx = 0 + -1A

Combine like terms: A + -1A = 0
0 + -3.14rx = 0 + -1A
-3.14rx = 0 + -1A
Remove the zero:
-3.14rx = -1A

Divide each side by '-3.14x'.
r = 0.3184713376x-1A

Simplifying
r = 0.3184713376x-1A
Solution
r = {0, 0.3184713376x-1A}