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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.
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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 Course 1 objective for today Learn to find the perimeter and missing side lengths of a polygon.
9-7 Perimeter Course 1 Insert Lesson Title Here Vocabulary perimeter
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.
9-7 Perimeter Course 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.
9-7 Perimeter Course 1
9-7 Perimeter Course 1 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.
9-7 Perimeter Course 1 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.
9-7 Perimeter Course 1 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.
9-7 Perimeter Course 1 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.
9-7 Perimeter Course 1 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.
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.
What we learned today! Learned to find the perimeter and missing side lengths of a polygon.