1. Warm Up 4/12 What 3D figure is created if the triangle below is rotated about the longer leg. Cone

2. Announcements Quiz next Tuesday Homework due Thursday Warm ups due Thursday

3. Prisms Prism: a polyhedron with exactly two congruent faces called bases that are parallel The other sides are called lateral faces. The other sides are called __________________________ faces.

4. Lateral v. Total Surface Area Lateral Surface Area: The sum of the areas of the lateral faces Total Surface Area: The sum of the lateral surface area and the areas of the two bases.

5. Example: What is the surface Area? Draw a net 12 20 12 1520 15

6. Surface Area of a Right Prism The formula for lateral surface area is S (lateral )=Ph The surface area of a right prism is S (total)=Ph+2B  B= area of the base  P=Perimeter of the base  H=height of the prism Why do we multiply the area of the base by 2?

7. Using Formulas to Find Surface Area SA= PH+2B P=3+4+5=12 H=6 B=1/2bh =1/2(3)(4) =6 SA=12(6)+2(6) =72+12 =84 square centimeters 5

8. Example SA Find the lateral surface area and surface area of the prism below: Lateral SA= PH P=5+12+13 =30 H=8 Later SA= 30(8) =240 inches squared SA=PH +2B B=1/2bh =1/2(12)(5) =30 SA=240+2(30) =300 inches squared 13

9. Homework Assignment: p 569 #1-7 all