1 / 21

9-7

9-7. Perimeter. Course 1. Warm Up. Problem of the Day. Lesson Presentation. 9-7. Perimeter. Course 1. Warm Up 1. What figure has four equal sides and four right angles? 2. What figure has eight sides? 3. What figure has five sides?. square. octagon. pentagon. 9-7. Perimeter.

freira
Download Presentation

9-7

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. 9-7 Perimeter Course 1 Warm Up Problem of the Day Lesson Presentation

  2. 9-7 Perimeter Course 1 Warm Up 1.What figure has four equal sides and four right angles? 2. What figure has eight sides? 3. What figure has five sides? square octagon pentagon

  3. 9-7 Perimeter Course 1 Problem of the Day Find the greatest perimeter possible when 6 identical unit squares are arranged to form a closed figure. Adjacent squares must share an entire side. 14 units

  4. 9-7 Perimeter Course 1 Learn to find the perimeter and missing side lengths of a polygon.

  5. 9-7 Perimeter Course 1 Insert Lesson Title Here Vocabulary perimeter

  6. 9-7 Perimeter Course 1 The perimeter of a figure is the distance around it. To find the perimeter you can add the lengths of the sides.

  7. 9-7 Perimeter Course 1 Additional Example 1: Finding the Perimeter of a Polygon Find the perimeter of the figure. Add all the side lengths. 2.8 + 3.6 + 3.5 + 3 + 4.3 The perimeter is 17.2 in.

  8. 9-7 Perimeter Course 1 Check It Out: Example 1 Find the perimeter of the figure. 3.3 in. 3.3 in. Add all the side lengths. 3.3 + 3.3 + 4.2 + 4.2 + 3 The perimeter is 18 in. 4.2 in. 4.2 in. 3 in.

  9. 9-7 Perimeter Course 1

  10. 9-7 Perimeter Course 1 Additional Example 2: Using a Formula to Find Perimeter Find the perimeter P of the rectangle. 12 cm 3 cm P = 2l+ 2w Substitute 12 for l and 3 for w. P = (2 • 12) + (2 • 3) P = 24 + 6 Multiply. P = 30 Add. The perimeter is 30 cm.

  11. 9-7 Perimeter Course 1 Check It Out: Example 2 Find the perimeter P of the rectangle. 15 cm 2 cm P = 2l + 2w Substitute 15 for l and 2 for w. P = (2 •15) + (2 •2) P = 30 + 4 Multiply. P = 34 Add. The perimeter is 34 cm.

  12. 9-7 Perimeter Course 1 Additional Example 3A: Finding Unknown Side Lengths and the Perimeter of a Polygon Find each unknown measure. What is the length of side a if the perimeter equals 1,471 mm? P = sum of side lengths 1,471 = 416 + 272 + 201 + 289 + a Use the values you know. Add the known lengths. 1,471 = 1,178 + a 1,471 – 1,178 = 1,178 + a – 1,178 Subtract 1,178 from both sides. 293 = a Side a is 293 mm long.

  13. 9-7 Perimeter Course 1 Additional Example 3B: Finding Unknown Side Lengths and the Perimeter of a Polygon Find each unknown measure. What is the perimeter of the polygon? First find the unknown side length. 72 cm Find the sides opposite side b. The length of side b = 50 + 22. Side b is 72 cm long. P = 72 + 55 + 50 + 33 + 22 + 22 Find the perimeter. P = 254 The perimeter of the polygon is 254 cm.

  14. 9-7 Perimeter Course 1 Additional Example 3C: Finding Unknown Side Lengths and the Perimeter of a Polygon The width of a rectangle is 19 cm. What is the perimeter of the rectangle if the length is 4 times the width? 4w 19 cm Find the length. l= 4w l = (4 •19) Substitute 19 for w. Multiply. l = 76

  15. 9-7 Perimeter Course 1 Additional Example 3C Continued 4w 19 cm Use the formula for the perimeter of a rectangle. P = 2l + 2w Substitute 76and 19. P = 2(76) + 2 (19) P = 152 + 38 Multiply. P = 190 Add. The perimeter of the rectangle is 190 cm.

  16. 9-7 Perimeter Course 1 Check It Out: Example 3A Find each unknown measure. What is the length of side a if the perimeter equals 1,302 mm? 212 mm 280 mm 250 mm a P = sum of side lengths 240 mm 1,302 = 212 + 280 + 250 + 240 + a Use the values you know. Add the known lengths. 1,302 = 982 + a 1,302 – 982 = 982 + a – 982 Subtract 982 from both sides. 320 = a Side a is 320 mm long.

  17. 9-7 Perimeter Course 1 Check It Out: Example 3B Find each unknown measure. What is the perimeter of the polygon? 12 m 8 m First find the unknown side length. 14 m 4 m Find the sides opposite side b. 6 m The length of side b = 12 + 4. 16 m b m Side b is 16 m long. P = 14 + 12 + 8 + 4 + 6 + 16 Find the perimeter. P = 60 The perimeter of the polygon is 60 m.

  18. 9-7 Perimeter Course 1 Check It Out: Example 3C The width of a rectangle is 13 cm. What is the perimeter of the rectangle if the length is 5 times the width? 5w 13 cm Find the length. l = 5w l = (5 •13) Substitute 13 for w. Multiply. l = 65

  19. 9-7 Perimeter Course 1 Check It Out: Example 3C Continued 65 cm 13 cm Use the formula for the perimeter of a rectangle. P = 2l + 2w Substitute 65and 13. P = 2(65) + 2 (13) P = 130 + 26 Multiply. P = 156 Add. The perimeter of the rectangle is 156 cm.

  20. 9-7 Perimeter 5 __ 6 Course 1 Insert Lesson Title Here Lesson Quiz: Part I Find each perimeter. 1.2. 3. What is the perimeter of a polygon with side lengths of 15 cm, 18 cm, 21 cm, 32 cm, and 26 cm? 9 cm 4 ft 112 cm

  21. 9-7 Perimeter Course 1 Insert Lesson Title Here Lesson Quiz: Part II 4. What is the perimeter of a rectangle with length 22 cm and width 8 cm? 5. The width of a rectangle is 12 in. What is the perimeter of the rectangle if the length is 7 in. longer than the width? 60 cm 62 in.

More Related