2. WARM UP Find the Lateral and Surface Area of the following figures. Leave your answers in terms of π 10 minutes End

3. TODAY’S OBJECTIVE Students will be able to find the surface area of pyramids, cones, and spheres

4. PYRAMID Definition: A Pyramid is a polyhedron with one polygonal base and triangular lateral faces that meet at a common vertex The Altitude of a Pyramid (or height) is the perpendicular segment from the vertex to the base. The SLANT HEIGHT (L) is the length of the altitude of a lateral face of the pyramid

5. PYRAMID FORMULAS

6. EX6: FIND LATERAL AND SURFACE AREAS LA = SA =

7. EX 7: FIND LA AND SA LA = SA =

8. CONES Definition: A cone is like a pyramid but has a circle base. The Altitude (or height) is the perpendicular distance from the vertex to the base. The slant height is the distance from the vertex to a point on the edge of the base.

9. CONE FORMULAS

10. EX 8: FIND LA AND SA LA = SA =

11. EX 8: FIND LA AND SA LA = SA =

12. REGULAR TETRAHEDRON A Tetrahedron is a polyhedron composed of four congruent, equilateral triangles

13. SURFACE AREA OF A REGULAR TETRAHEDRON A Net is a two-dimensional pattern that can be folded into a 3-D figure (We’ll look at more tomorrow) Lets look at a net for a regular tetrahedron. How can we find the surface area of a regular tetrahedron? or

14. EXAMPLE Calculate the surface area of a regular tetrahedron with an edge of 5cm

15. SPHERE Definition: A Sphere is the set of all points in space equidistant from a given point (the center) Definition: The Great Circle is the largest cross section (circle) of a sphere and shares the same radius and center as the sphere Center Great Circle

16. SURFACE AREA OF A SPHERE Find the Surface Area of the following spheres in terms of π Ex 1: r = 14 Ex 2: d = 12 Ex 3: C = 36π Ex 4: C = 52π

17. CLASSWORK Arrange desks in groups As a group, complete page 3 of Unit 10 packet (skip #1 of right side) and do SA of 1-6 on page 5 Be prepared to have your work displayed on doc cam!

18. HOMEWORK 1.Complete the left side of page 3 and number 3 from the right side. 2.Find the Surface Area of each sphere on page 5 (1-6) QUIZ TOMORROW!