1 / 22

Warm Up Find the perimeter and area of each polygon.

Warm Up Find the perimeter and area of each polygon. 1. a rectangle with base 14 cm and height 9 cm. P = 46 cm; A = 126 cm 2. 10-4. Surface Area of Prisms and Cylinders. Holt Geometry.

marenda-faunus
Télécharger la présentation

Warm Up Find the perimeter and area of each polygon.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Warm Up Find the perimeter and area of each polygon. 1.a rectangle with base 14 cm and height 9 cm P = 46 cm; A = 126 cm2

  2. 10-4 Surface Area of Prisms and Cylinders Holt Geometry

  3. A lateral faceis not a base. The edges of the base are called base edges. A lateral edgeis not an edge of a base. The lateral faces of a right prismare all rectangles. An oblique prismhas at least one nonrectangular lateral face.

  4. An altitudeof a prism or cylinder is a perpendicular segment joining the planes of the bases. The heightof is the length of an altitude. Surface areais the total area of all faces and curved surfaces of a three-dimensional figure. The lateral area of a prism is the sum of the areas of the lateral faces.

  5. The surface area of a right rectangular prism S = 2ℓw + 2wh + 2ℓh.

  6. Example 1A: Finding Lateral Areas and Surface Areas of Prisms Find the lateral area and surface area of the right rectangular prism. Round to the nearest tenth, if necessary. L = Ph P = 2(9) + 2(7) = 32 ft = 32(14) = 448 ft2 S = Ph + 2B = 448 + 2(7)(9) = 574 ft2

  7. Check It Out! Example 1 Find the lateral area and surface area of a cube with edge length 8 cm. L = Ph = 32(8) = 256 cm2 P = 4(8) = 32 cm S = Ph + 2B = 256 + 2(8)(8) = 384 cm2

  8. The lateral surfaceof a cylinder is the curved surface that connects the two bases. The axis of a cylinderis the segment with endpoints at the centers of the bases. The axis of a right cylinderis perpendicular to its bases. The axis of an oblique cylinderis not perpendicular to its bases.

  9. Example 2A: Finding Lateral Areas and Surface Areas of Right Cylinders Find the lateral area and surface area of the right cylinder. Give your answers in terms of . The radius is half the diameter, or 8 ft. L = 2rh = 2(8)(10) = 160 in2 S = L + 2r2 = 160 + 2(8)2 = 288 in2

  10. Example 2B: Finding Lateral Areas and Surface Areas of Right Cylinders Find the lateral area and surface area of a right cylinder with circumference 24 cm and a height equal to half the radius. Give your answers in terms of . Step 1 Use the circumference to find the radius. Circumference of a circle C = 2r Substitute 24 for C. 24 = 2r Divide both sides by 2. r = 12

  11. Example 2B Continued Find the lateral area and surface area of a right cylinder with circumference 24 cm and a height equal to half the radius. Give your answers in terms of . Step 2 Use the radius to find the lateral area and surface area. The height is half the radius, or 6 cm. L = 2rh = 2(12)(6) = 144 cm2 Lateral area S = L + 2r2 = 144 + 2(12)2 = 432 in2 Surface area

  12. Example 3: Finding Surface Areas of Composite Three-Dimensional Figures Find the surface area of the composite figure.

  13. A right triangular prism is added to the rectangular prism. The surface area of the triangular prism is The surface area of the rectangular prism is . Two copies of the rectangular prism base are removed. The area of the base is B = 2(4) = 8 cm2. . S = (rectangular prism surface area) + (triangular prism surface area) – 2(rectangular prism base area) S = 52 + 36 – 2(8) = 72 cm2

  14. Check It Out! Example 3 Find the surface area of the composite figure. Round to the nearest tenth.

  15. Remember! Always round at the last step of the problem. Use the value of  given by the  key on your calculator.

  16. Example 4: Exploring Effects of Changing Dimensions The edge length of the cube is tripled. Describe the effect on the surface area.

  17. 24 cm Example 4 Continued original dimensions: edge length tripled: S = 6ℓ2 S = 6ℓ2 = 6(24)2 = 3456 cm2 = 6(8)2 = 384 cm2 Notice than 3456 = 9(384). If the length, width, and height are tripled, the surface area is multiplied by 32, or 9.

  18. Example 5: Recreation Application A sporting goods company sells tents in two styles, shown below. The sides and floor of each tent are made of nylon. Which tent requires less nylon to manufacture?

  19. Example 5 Continued Pup tent: Tunnel tent: The tunnel tent requires less nylon.

  20. Lesson Quiz: Part I Find the lateral area and the surface area of each figure. Round to the nearest tenth, if necessary. 1. a cube with edge length 10 cm 2. a regular hexagonal prism with height 15 in. and base edge length 8 in. 3. a right cylinder with base area 144 cm2 and a height that is the radius L = 400 cm2 ; S = 600 cm2 L = 720 in2; S 1052.6 in2 L 301.6 cm2; S = 1206.4 cm2

  21. Lesson Quiz: Part II 4. A cube has edge length 12 cm. If the edge length of the cube is doubled, what happens to the surface area? 5. Find the surface area of the composite figure. The surface area is multiplied by 4. S = 3752 m2

More Related