110k views
2 votes
What is the surface area of this cylinder? Please show steps!

What is the surface area of this cylinder? Please show steps!-example-1

2 Answers

6 votes

Answer:

251.33

Explanation:

the formula is π r-squared h

so the formula for this question is π (2 squared)(20)

you will square 2 to get 4 then multiply that by π then lastly multiply by 20

User RHA
by
9.2k points
6 votes

Answer:

area = (exact) 88pi ft^2 or (approximate) 276 ft^2

Explanation:

The surface area of a cylinder is the sum of the areas of the bases, two circles, and the lateral area which is a rectangle.

Each base is a circle, and the two bases are congruent, so find the area of one base and multiply by 2.

The lateral area is a rectangle. You need to find the length and width of the rectangle. Think of a can of food with a label wrapped around. If you make a vertical cut from one base to the other, and you unwrap the label, you will see that the lateral surface of a cylinder is a rectangle that has the height of the cylinder as its length, and the circumference of the base are its width.

area of circle = pi *r^2

area of rectangle = length * width

length of rectangle: length = 2(pi)r

width of rectangle: width = height = h

total area of cylinder = area of bases + lateral area

total area of cylinder = 2 * pi *r^2 + 2(pi)r * h

total area of cylinder = 2 * pi * (2 ft)^2 + 2 * pi * 2 ft * 20 ft

total area of cylinder = 8pi ft^2 + 80pi ft^2

total area of cylinder = 88pi ft^2

The exact area is 88pi ft^2.

If you need an approximate area, then use 3.14 for pi.

area = 88 * 3.14 ft^2

area = 276 ft^2

User Unleashed
by
7.7k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories