How can you use the net of a cylinder to determine the surface area of a cylinder?

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1. Scroll down to the blue box titled, “Find the Surface Area of a Cylinder.”
2. Click Play to view the animation of the net.
3. Click Next to work through a practice problem. Use your calculator to help you with computation. Follow the on-screen prompts to proceed through the steps of the problem.
4. At the end of the problem, you will see a summary screen. You may wish to copy that information into your notes for your future reference.

Example: The net of a cylinder is given below. Find the total surface area.

Answer the following questions.

• The formula for the area of a circle is _____?____.
  
  Interactive popup. Assistance may be required. Check Your Answer A = πr²
  
  
• The radius of the circle is ___?___ units.
  
  Interactive popup. Assistance may be required. Check Your Answer 3
  
  
• The area of the circle is ___?___.
  
  Interactive popup. Assistance may be required. Check Your Answer A = π3² = 9π units²
  
  
• The formula for the area of a rectangle is ____?_____ .
  
  Interactive popup. Assistance may be required. Check Your Answer A = l · w = b · h
  
  
• The length or base of the rectangle is ____?____ units.
  
  Interactive popup. Assistance may be required. Check Your Answer 6π
  
  
• The width or height of the rectangle is ___?___ units.
  
  Check Your Answer 7
  
  
• The area of the rectangle is ___?____.
  
  Interactive popup. Assistance may be required. Check Your Answer A = 6π ·7 = 42π units²
  
  
• To find the total surface area of the cylinder, add the area of the two circles and the area of the ____?___.
  
  Interactive popup. Assistance may be required. Check Your Answer rectangle
  
  
• The total surface area is ___?____.
  
  Interactive popup. Assistance may be required. Check Your Answer 2(9π) + 42π = 18π + 42π = 60π units²