2. Surface Area of a Prisms Remember: Prisms are 3 dimensional shapes that have a constant cross-sectional area. Triangular-based prism Rectangular-based prism Pentagonal-based prism Hexagonal-based prism Octagonal-based prism Circular-based prism Cylinder Cuboid

3. Surface area of prisms. Diagrams Not to scale To find the surface area of a prism, find the area of all the faces and add them together 10 cm 4 cm 3 cm Surface area = 2 x 3 x 10 + 2 x 4 x 3 + 2 x 4 x 10 = 60 + 24 + 80 = 164 cm 2 14 cm 8 cm 2 cm 5 cm 2 cm 2 x 8 x 14 = 224 (top and bottom) 2 x 8 x 7 = 112 (L and R side views) 2 x 14 x 2 = 56 Surface area = 412 cm 2 2 x 5 x 2 = 20 2 1

4. Find the surface area of the following prisms. Diagrams Not to scale 3 mm 4 mm 2 mm 4 2.5 m 6 m 3 m 4 m 2.5 m 2 x 6 x 3 = 36 (top and bottom) 2 x 4 x 3 = 24 (L and R sides) 2 x 6 x 2.5 = 30 2 x 2.5 x 1.5 = 7.5 Surface area = 97.5 cm 2 3 5 mm 3 x rectangles give: 5 x 2 + 4 x 2 + 3 x 2 = 24 2 x triangles give: ½ (4 x 3) x 2 = 12 Surface area = 36 mm 2

5. Now try these. 6 5 10’’ 6’’ 5’’ 3’’ 2 x 10 x 5 = 100 (T and B) 2 x 6 x 5 = 60 (L and R) 2’’ Front and back gives: 2 x (10 x 6 - 2 x 3) = 108 2 x 5 x 3 = 30 Surface area = 298 inches 2 12 ft 5 ft 13 ft 2 ft 3 x rectangles give: 13 x 2 + 12 x 2 + 5 x 2 = 60 2 x triangles give: ½ (12 x 5) x 2 = 60 Surface area = 120 ft 2 Diagrams Not to scale

6. Worksheet 1 10 cm 4 cm 3 cm 14 cm 8 cm 2 cm 5 cm 2 cm 2 1 Surface Area of a Prism

7. Worksheet 2 3 mm 4 mm 2 mm 4 2.5 m 6 m 3 m 4 m 2.5 m 3 5 mm Surface Area of a Prism

8. Worksheet 3 6 5 10’’ 6’’ 5’’ 3’’ 2’’ 12 ft 5 ft 13 ft 2 ft Surface Area of a Prism