1. GEOMETRY Success depends upon previous preparation and without such preparation there is sure to be failure. Confucius Today: 12.2 Instruction Practice

2. 12.2 Surface Areas of Prisms and Cylinders Objectives: Know the terms for prisms Find the surface area for prisms Know the terms for cylinders Find the surface area for cylinders Vocabulary: prism, bases, lateral faces, lateral area, surface area, cylinder, height

3. Prism: a polyhedron with two congruent bases that are parallel. The other faces (called lateral faces) are parallelograms made by connecting the bases. Third dimension is height of WHOLE FIGURE. Lateral Area: Area of Lateral Faces Surface Area: Sum of ALL Faces

4. General Formula for Surface Area: SA = 2B + Ph where B = Area of Base, P = Perimeter of Base and h = height of whole figure Find the surface area of the figure: 10 in 6 in 4 in

5. General Formula for Surface Area: SA = 2B + Ph where B = Area of Base, P = Perimeter of Base and h = height of whole figure Find the surface area of the figure: SA = 1979 cm 2

6. You are working for Macy’s wrapping presents over the holiday season. You receive an order to wrap 15 boxes that are 12 in by 5 in by 2.5 in each. The roll of wrapping paper you have covers 20 square feet, do you have enough to wrap all the presents?

7. Find the surface area of the figure: Not a prism… but close Cylinder: a solid with two circular bases that are parallel. General Formula for Surface Area: SA = 2B + Ph where B = Area of Base, P = Perimeter of Base and h = height of whole figure What needs to change? General Formula for Surface Area: SA = 2B + Ch where B = Area of Base, C = Circumference and h = height of whole figure

8. Find the surface area of a right cylinder that has a diameter of 10” and a height of 10”. EXACT SA = 150  in 2 Approx SA = 471 in 2

9. If the surface area of a right cylinder is 648  feet squared and the height is 15 feet, find the radius of the base.

10. Assignment:  12.2 p 850 #13, 15, 17, 19, 27, 33, 37, 45  Quiz 12.1 – 12.3 Friday GEOMETRY Success depends upon previous preparation and without such preparation there is sure to be failure. Confucius