Question

What is the surface area of the cylinder with height 7 cm and radius 5 cm? Round

Answer 1

Answer:

376.991 cm²

Step-by-step explanation:

$SA_{cylinder} = 2\pi r^{2} + 2\pi rh$

Surface Area = 2π(5²) + 2π(5)(7)

                      = 50π + 70π

                      = 120π

                      = 376.9911184... ≈ 376.991

Derive Surface Area of A Cylinder

If you take a look at a net of a cylinder, you can see it is composed of two circles(bases) and a rectangular strip with the length of the diameter of the circle

The formula for the area of a circle = πr², and since there are 2, it is 2πr²

The formula for circumference of a circle = 2πr, and since we are multiplying that by the height by the height of the cylinder, it is 2πrh

∴ 2πr² + 2πrh