Solve for the indicated letter.
-Solve $S=\pi r h+\pi r^{2}$ for $r$.
A) $r=\frac{-\pi \mathrm{h} \pm \sqrt{\pi \mathrm{h}+4 \pi \mathrm{S}}}{2 \pi}$
B) $r=\frac{-\pi \pm \sqrt{\pi^{2}+4 \pi S}}{2 \pi}$
C) $r=\frac{-\pi h \pm \sqrt{\pi^{2} h^{2}-4 \pi S}}{2 \pi}$
D) $r=\frac{-\pi \mathrm{h} \pm \sqrt{\pi^{2} \mathrm{~h}^{2}+4 \pi \mathrm{S}}}{2 \pi}$

Question

Quizplus · Accepted Answer

To solve for $r$, we rearrange the equation $S=\pi r h+\pi r^{2}$ into a quadratic form $0=\pi r^{2} + \pi h r - S$. Using the quadratic formula $r=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$ with $a=\pi$, $b=\pi h$, and $c=-S$, we get $r=\frac{-\pi h \pm \sqrt{\pi^{2} h^{2}+4\pi S}}{2\pi}$.

Solve for the Indicated Letter S=πrh+πr2S=\pi r h+\pi r^{2}S=πrh+πr2 For rrr A)

Solve for the Indicated Letter $S=\pi r h+\pi r^{2}$ For $r$
A)