a cylinder has a base radius of 7 cm and a height of 20 cm calculate the total surface area when closed on one side

Answer: 189π sq. cm = 594 sq. cm.

Step-by-step explanation:

Calculate the base area by using the formula for a circle's area: A = π * r^2. If the radius of the cylinder is 7, for instance, the area of one base is π * 7^2 or 49π

Multiply the circumference of the base by the cylinder's height to determine the lateral area's surface area. If you were to tear the cylinder open and lay it flat on a table, you would discover the lateral area is simply a rectangle whose length is the base's circumference and whose width is the cylinder's height. Given a radius of 7, the circumference is 2 * π * 7, or 14π. Given a height of 20, multiply 20π by 7 to obtain a lateral surface area of 140π.

Add the base area to the lateral surface area to find the total surface area. Given the example, add 49π to 140π to obtain a total area of 189π.