Surface Area of Pyramids Return to table of contents

Surface Area of Pyramids What is a pyramid? Polyhedron with one base and triangular faces that meet at a vertex How do you find Surface Area? Sum of the areas of all the surfaces of a 3-D Figure click to reveal click to reveal

Find the Surface Area. 17.5 cm go on to see steps 7 cm 8 cm

Find the Surface Area. Bottom Front/Back Left/Right Rectangle 8 cm 7 cm 17.5 cm 8 cm Bottom Rectangle 8 x 7 56 Front/Back Triangles Left/Right Triangles Surface Area 56 140 + 122.5 318.5 cm2

Find the surface area of a square pyramid with base edge of 4 inches and triangle height of 3 inches. 4 in 3 in Base 4 x 4 16 4 Triangles Surface Area 16 + 24 40 in2 click to reveal click to reveal click to reveal

Find the surface area. Be sure to look at the base to see if it is an equilateral or isosceles triangle (making all or two of the side triangles equivalent!). Triangles (all equal) Base click to reveal click to reveal 6 in 4 in 3.5 in Surface Area 7 + 36 43 in2 4 in 4 in click to reveal

42 Which has a greater Surface Area, a square pyramid with a base edge of 8 in and a height of 4 in or a cube with an edge of 5 in? A Square Pyramid B Cube Answer: B Square Pyramid Cube Bases 4 Triangles 6 faces A = s 2 A = (1/2)bh x 4 A = s 2 x 6 A = 82 A = (1/2)(8)(4) x 4 A = 52 x 6 A = 64 in2 A = 64 in2 A = 150 in2 SA= 128 in2

43 Find the Surface Area of a triangular pyramid with base edges of 8 in, base height of 4 in and a slant height of 10 in. 8 in 10 in 6.9 in Answer: 147.6 Bases 3 Triangles A = (1/2)bh A = (1/2)bh x 3 A = (1/2)(8)(6.9) A = (1/2)(8)(10) x 3 A = 27.6 A = 120 SA= 27.6 + 120 = 147.6 in2

44 Find the Surface Area. 11 m 12 m 6.7 m 9 m 9 m Answer: 205.2 Bases 3 Triangles A = (1/2)bh A = (1/2)bh x 2 + (1/2) bh A = (1/2)(12)(6.7) A = (1/2)(9)(11) x 2 + (1/2)(12)(11) A = 40.2 A = 99 + 66 A = 165 SA= 40.2 + 165 = 205.2 in2 9 m 9 m