Solve for l P=4pilr^2

$P = 4 π l r^{2}$

Rewrite the equation as $4 π l r^{2} = P$ .

$4 π l r^{2} = P$

Divide each term in $4 π l r^{2} = P$ by $4 π r^{2}$ and simplify.

Divide each term in $4 π l r^{2} = P$ by $4 π r^{2}$ .

$\frac{4 π l r^{2}}{4 π r^{2}} = \frac{P}{4 π r^{2}}$

Simplify the left side.

Cancel the common factor of $4$ .

Cancel the common factor.

$\frac{4 π l r^{2}}{4 π r^{2}} = \frac{P}{4 π r^{2}}$

Rewrite the expression.

$\frac{π l r^{2}}{π r^{2}} = \frac{P}{4 π r^{2}}$

Cancel the common factor of $π$ .

Cancel the common factor.

$\frac{π l r^{2}}{π r^{2}} = \frac{P}{4 π r^{2}}$

Rewrite the expression.

$\frac{l r^{2}}{r^{2}} = \frac{P}{4 π r^{2}}$

Cancel the common factor of $r^{2}$ .

Cancel the common factor.

$\frac{l r^{2}}{r^{2}} = \frac{P}{4 π r^{2}}$

Divide $l$ by $1$ .

$l = \frac{P}{4 π r^{2}}$