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Learn how to find the surface area of various three-dimensional figures such as prisms, pyramids, and cylinders in this interactive course.
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Surface Area 10-9 Course 1 Warm Up Problem of the Day Lesson Presentation
Surface Area 10-9 Course 1 Warm Up Identify the figure described. 1.two parallel congruent faces, with the other faces being parallelograms 2. a polyhedron that has a vertex and a face at opposite ends, with the other faces being triangles prism pyramid
Surface Area 10-9 Course 1 The surface area of a three-dimensional figure is the sum of the areas of its surfaces. To help you see all the surfaces of a three-dimensional figure, you can use a net. A net is the pattern made when the surface of a three-dimensional figure is layed out flat showing each face of the figure.
Surface Area 10-9 Course 1 Additional Example 1A: Finding the Surface Area of a Prism Find the surface area S of the prism. Method 1: Use a net. Draw a net to help you see each face of the prism. Use the formula A = lw to find the area of each face.
Surface Area 10-9 Add the areas of each face. Course 1 Additional Example 1A Continued A: A = 5 2 = 10 B: A = 12 5 = 60 C: A = 12 2 = 24 D: A = 12 5 = 60 E: A = 12 2 = 24 F: A = 5 2 = 10 S = 10 + 60 + 24 + 60 + 24 + 10 = 188 The surface area is 188 in2.
Surface Area 10-9 Course 1 Additional Example 1B: Finding the Surface Area of a Prism Find the surface area S of each prism. Method 2: Use a three-dimensional drawing. Find the area of the front, top, and side, and multiply each by 2 to include the opposite faces.
Surface Area 10-9 Course 1 Additional Example 1B Continued Front: 9 7 = 63 63 2 = 126 Top: 9 5 = 45 45 2 = 90 Side: 7 5 = 35 35 2 = 70 S = 126 + 90 + 70 = 286 Add the areas of each face. The surface area is 286 cm2.
Surface Area 10-9 Course 1 Check It Out: Example 1A Find the surface area S of the prism. Method 1: Use a net. 3 in. A 3 in. 6 in. 3 in. 6 in. 11 in. 6 in. 3 in. 11 in. B D E C 3 in. F Draw a net to help you see each face of the prism. Use the formula A = lw to find the area of each face.
Surface Area 10-9 Add the areas of each face. Course 1 Check It Out: Example 1A A: A = 6 3 = 18 3 in. A B: A = 11 6 = 66 3 in. 6 in. 3 in. 6 in. C: A = 11 3 = 33 11 in. D: A = 11 6 = 66 B D E C E: A = 11 3 = 33 3 in. F F: A = 6 3 = 18 S = 18 + 66 + 33 + 66 + 33 + 18 = 234 The surface area is 234 in2.
Surface Area 10-9 Find the area of the front, top, and side, and multiply each by 2 to include the opposite faces. Course 1 Check It Out: Example 1B Find the surface area S of each prism. Method 2: Use a three-dimensional drawing. top side front 8 cm 10 cm 6 cm
Surface Area 10-9 Course 1 Check It Out: Example 1B Continued top side front 8 cm 10 cm 6 cm Front: 8 6 = 48 48 2 = 96 Top: 10 6 = 60 60 2 = 120 Side: 10 8 = 80 80 2 = 160 S = 160 + 120 + 96 = 376 Add the areas of each face. The surface area is 376 cm2.
Surface Area 10-9 Course 1 The surface area of a pyramid equals the sum of the area of the base and the areas of the triangular faces. To find the surface area of a pyramid, think of its net.
Surface Area 10-9 S = s2 + 4 ( bh) 1 1 __ __ S = 72 + 4 ( 78) 2 2 Substitute. Course 1 Additional Example 2: Finding the Surface Area of a Pyramid Find the surface area S of the pyramid. S = area of square + 4 (area of triangular face) S = 49 + 4 28 S = 49 + 112 S = 161 The surface area is 161 ft2.
Surface Area 10-9 S = s2 + 4 ( bh) 1 1 __ __ S = 52 + 4 ( 510) 2 2 Substitute. Course 1 Check It Out: Example 2 Find the surface area S of the pyramid. S = area of square + 4 (area of triangular face) 10 ft 5 ft 5 ft 10 ft S = 25 + 4 25 5 ft S = 25 + 100 S = 125 The surface area is 125 ft2.
Surface Area 10-9 Helpful Hint To find the area of the curved surface of a cylinder, multiply its height by the circumference of the base. Course 1 The surface area of a cylinder equals the sum of the area of its bases and the area of its curved surface.
Surface Area 10-9 Course 1 Additional Example 3: Finding the Surface Area of a Cylinder Find the surface area S of the cylinder. Use 3.14 for , and round to the nearest hundredth. ft S = area of lateral surface + 2 (area of each base) S = h (2r) + 2 (r2) Substitute. S = 7 (2 4)+ 2 (42)
Surface Area 10-9 Course 1 Additional Example 3 Continued Find the surface area S of the cylinder. Use 3.14 for , and round to the nearest hundredth. S = 7 8 + 2 16 S 7 8(3.14) + 2 16(3.14) Use 3.14 for . S 7 25.12 + 2 50.24 S 175.84 + 100.48 S 276.32 The surface area is about 276.32 ft2.
Surface Area 10-9 Course 1 Check It Out: Example 3 Find the surface area S of the cylinder. Use 3.14 for , and round to the nearest hundredth. 6 ft 9 ft S = area of lateral surface + 2 (area of each base) S = h (2r) + 2 (r2) Substitute. S = 9 (2 6)+ 2 (62)
Surface Area 10-9 Course 1 Check It Out: Example 3 Continued Find the surface area S of the cylinder. Use 3.14 for , and round to the nearest hundredth. S = 9 12 + 2 36 S 9 12(3.14) + 2 36(3.14) Use 3.14 for . S 9 37.68 + 2 113.04 S 339.12 + 226.08 S 565.2 The surface area is about 565.2 ft2.
Surface Area 10-9 Course 1 Insert Lesson Title Here Lesson Quiz Find the surface area of each figure. Use 3.14 for . 1. rectangular prism with base length 6 ft, width 5 ft, and height 7 ft 2. cylinder with radius 3 ft and height 7 ft 3. Find the surface area of the figure shown. 214 ft2 188.4 ft2 208 ft2