The answer is 7. The formula to find the surface area of a cylinder is [tex]a =2 \pi {r}^{2} + 2\pi rh[/tex] Plug in the givens: [tex]615.44 = 2 \times 3.14 \times {7}^{2} + 2 \times 3.14 \times 7 \times h[/tex] Eliminate the exponents: [tex]615.44 = 2 \times 3.14 \times 49 + 2 \times 3.14 \times 7 \times h[/tex] Multiply the numbers: [tex]615.44 = 307.72 + 43.96h[/tex] Subtract 307.72 from both sides: [tex]43.96h = 307.72[/tex] Divide both sides by 43.96: [tex]h = 7[/tex]
