1. A cake is a rectangular prism with height 4 inches and base 12 inches by 15 inches. Wallace wants to apply frosting to the sides and the top of the cake. What is the surface area of the part of the cake that will have frosting?
Problem of the Day

2. Section 12-2b Surface Areas of Cylinders

3. Then
Now
Objectives
You found the lateral area and surface area of prisms.
Find the lateral area and surface area of cylinders.

4. Common Core State Standards
Content Standards
G.MG.3 – Apply geometric methods to solve problems.
Mathematical Practices
1) Make sense of problems and persevere in solving them.
6) Attend to precision.
Common Core State Standards

5. Cylinder

7. Find the lateral area and surface area of the cylinder.
Example 3

8. Find the lateral area and surface area of the cylinder.
Example 3

9. Find the lateral area and surface area of the cylinder.
Example 3

10. Find the diameter of a base of a cylinder if the surface area is 464π square centimeters and the height is 21 centimeters.
Example 4

11. Sheree used the rectangular piece of felt shown to cover the curved surface of her cylindrical pencil holder. What is the radius of the pencil holder?
Example 4

12. p.850 # 17 – 27, 39
Homework