Question

Find the area of the top and lateral surfaces of a cylindrical water
tank with radius 20 ft and height 30 ft.

Question: draw and label a diagram of the water tank

Answer 1

the top is just a circle.

\[A_{\text{circle}}= \pi\cdot r^2 =\pi\cdot \frac{ d^2 }{ 4 }\]

the lateral are is just a rectangle rolled into a circular shape.

the height of the cylinder is like the width of the rectangle and the circumference of the cylinder is like the length of the rectangle.

So the lateral area is:

\[A=l\cdot w = (2\pi r)\cdot h\]

Answer 2

Thankyou! @pgpilot326

Answer 3

you're welcome!