What is the area of the lateral surface of the cylinder if the base diameter is 4 cm, and the generatrix is 9 cm?

A cylinder is a geometric body formed by rotating a rectangle around one of its sides.

In order to calculate the area of the lateral surface of the cylinder, you need to multiply the circumference of its base by the generatrix, which is equal to the height:

Sb.p. = L h.

Since the circumference of the base is equal to:

L = 2πr, then the formula for the lateral surface area can be expressed as follows:

Sb.p. = 2πrh;

r = d / 2;

r = 4/2 = 2 cm;

Sb.p. = 2 · 3.14 · 2 · 9 = 113.04 cm2.

Answer: the area of the lateral surface of the cylinder is 113.04 cm2.