1. Obj: Find the lateral & surface area of cones (3.12.3)

2. What is a cone? Shaped like a teepee Base is a circle and has a vertex point Two types: right cone & oblique cone

3. Cheer Up, Cones are fun!

4. What is a slant height (l)? The measure of any segment joining the vertex of a right cone to the edge of the circular base.

5. What is the height (h)? The measure of the altitude is the height of the cone. Segment from the vertex that is perpendicular to the base.

6. What is the lateral area of a cone? The sector of the circle R = radius, l = slant height L = πrl

7. What is the surface area of a cone? The lateral area plus the circular base T = πrl + πr 2

8. Do you see a similarity? Prism Perimeter(Height) + 2(Bases) Pyramid ½(Perimeter)(Height) + Base

9. Do you see a similarity? Cylinder 2(Pi)(Radius)(Height) + 2(Pi)(Radius) 2 Cone (Pi)(Radius)(Slant Height) + (Pi)(Radius) 2

10. Do you see a similarity? Pyramid is ½ the Surface Area of a Prism Cone is ½ the Surface Area of a cylinder