Geometry 1 4 Introduction to Perimeter and Area

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Geometry 1. 4 Introduction to Perimeter, and Area in the coordinate plane.

Geometry 1. 4 Introduction to Perimeter, and Area in the coordinate plane.

Topic/Objectives: • Find the perimeter and area of common plane figures. • To classify

Topic/Objectives: • Find the perimeter and area of common plane figures. • To classify polygons. • To compare convex and concave polygons. 14 February 2022 Geometry 1. 4 Perimeter, Area 2

Square Perimeter S P = 4 s S Area A = s 2 14

Square Perimeter S P = 4 s S Area A = s 2 14 February 2022 Geometry 1. 4 Perimeter, Area 3

Square Problem Each side of a square measures 2. 5 m. Find its perimeter

Square Problem Each side of a square measures 2. 5 m. Find its perimeter and its area. P = 4(2. 5) = 10 m A = 2. 52 = 6. 25 m 2 2. 5 m 14 February 2022 Area is a square measure. Geometry 1. 4 Perimeter, Area 4

Rectangle Perimeter w P = 2 l + 2 w l Area A =

Rectangle Perimeter w P = 2 l + 2 w l Area A = lw 14 February 2022 Geometry 1. 4 Perimeter, Area 5

Rectangle Problem 4 ft Find the perimeter and the area. 2. 1 ft P

Rectangle Problem 4 ft Find the perimeter and the area. 2. 1 ft P = 2(4) + 2(2. 1) = 8 + 4. 2 = 12. 2 ft A = 4(2. 1) = 8. 4 ft 2 14 February 2022 Geometry 1. 4 Perimeter, Area 6

Triangle Perimeter a c h P=a+b+c Area b 14 February 2022 Geometry 1. 4

Triangle Perimeter a c h P=a+b+c Area b 14 February 2022 Geometry 1. 4 Perimeter, Area 7

Triangle Problem 3 in 8 in 2 in 10 in Find the perimeter and

Triangle Problem 3 in 8 in 2 in 10 in Find the perimeter and the area. P = 3 + 10 + 8 = 21 in A = ½ (10)(2) = 10 in 2 14 February 2022 Geometry 1. 4 Perimeter, Area 8

Problem Solving Steps 1. Sketch 2. Label 3. Formulas 4. Reason 5. Conclusion 6.

Problem Solving Steps 1. Sketch 2. Label 3. Formulas 4. Reason 5. Conclusion 6. Check 14 February 2022 Geometry 1. 4 Perimeter, Area 9

Problem 1 A homeowner needs to fertilize a rectangular shaped yard that measures 20

Problem 1 A homeowner needs to fertilize a rectangular shaped yard that measures 20 ft by 30 ft. Each bag of fertilizer covers 150 square feet. How many bags of fertilizer will he need? 1. Sketch 30 ft. A=? 14 February 2022 Geometry 1. 4 Perimeter, Area 2. label 20 ft 10

Problem 1 Continued A homeowner needs to fertilize a rectangular shaped yard that measures

Problem 1 Continued A homeowner needs to fertilize a rectangular shaped yard that measures 20 ft by 30 ft. Each bag of fertilizer covers 150 square feet. How many bags of fertilizer will he need? 3. Formula: A = LW a = 30(20) = 600 FT 2 30 ft. A=? 14 February 2022 Geometry 1. 4 Perimeter, Area 20 ft 11

Problem 1 Continued A homeowner needs to fertilize a rectangular shaped yard that measures

Problem 1 Continued A homeowner needs to fertilize a rectangular shaped yard that measures 20 ft by 30 ft. Each bag of fertilizer covers 150 square feet. How many bags of fertilizer will he need? 30 ft. A = 600 FT 2 14 February 2022 4. Reason: Each bag covers 150 sq ft, and he needs to cover 600 sq ft. 600 150 = 4 20 ft Geometry 1. 4 Perimeter, Area 12

Problem 1 Conclusion A homeowner needs to fertilize a rectangular shaped yard that measures

Problem 1 Conclusion A homeowner needs to fertilize a rectangular shaped yard that measures 20 ft by 30 ft. Each bag of fertilizer covers 150 square feet. How many bags of fertilizer will he need? 5. Conclusion: He needs to buy 4 bags of fertilizer. 30 ft. A = 600 FT 2 14 February 2022 6. Check: 4 150 = 600 20 ft Geometry 1. 4 Perimeter, Area 13

EX: Determine the perimeter of the polygon with the given vertices. A(-4, -1), B(1,

EX: Determine the perimeter of the polygon with the given vertices. A(-4, -1), B(1, 4), C(4, 1), D(-1, -4) B Sketch Label C A D Formulas: Use distant formula to find each length. 14 February 2022 Geometry 1. 4 Perimeter, Area 14

EX: Find the area of the polygon with the given vertices. (-2, 3), (3,

EX: Find the area of the polygon with the given vertices. (-2, 3), (3, -3), (-2, -3) A = ½ bh A = 15 6 5 14 February 2022 Geometry 1. 4 Perimeter, Area 15

Convex vs Concave 14 February 2022 Geometry 1. 4 Perimeter, Area 16

Convex vs Concave 14 February 2022 Geometry 1. 4 Perimeter, Area 16

Problem 2 You are making a mat for a picture. The picture is 8

Problem 2 You are making a mat for a picture. The picture is 8 inches wide and 10 inches high. The mat is to have a width of 2 inches. What is the area of the mat? 8 2 14 February 2022 10 2 Geometry 1. 4 Perimeter, Area 17

Problem 2 Continued You are making a mat for a picture. The picture is

Problem 2 Continued You are making a mat for a picture. The picture is 8 inches wide and 10 inches high. The mat is to have a width of 2 inches. What is the area of the mat? Think: Larger mat, cut away the inside… 14 February 2022 Geometry 1. 4 Perimeter, Area 18

Problem 2 Continued You are making a mat for a picture. The picture is

Problem 2 Continued You are making a mat for a picture. The picture is 8 inches wide and 10 inches high. The mat is to have a width of 2 inches. What is the area of the mat? We need to know the area of the outer rectangle. 12 Left over Area = 8 Outer Area = 168 – 80 = 88 in 2 12 14 = 168 Inner Area = 10 2 14 8 10 = 80 14 February 2022 2 Geometry 1. 4 Perimeter, Area 19

Problem 3: You do it. You are making a triangular shaped window. The height

Problem 3: You do it. You are making a triangular shaped window. The height of the window is 18 inches and the area will be 297 square inches. What will the length of the base of the window be? 18 b The base will be 33 in. 14 February 2022 Geometry 1. 4 Perimeter, Area 20

Write a Summary 14 February 2022 Geometry 1. 4 Perimeter, Area 21

Write a Summary 14 February 2022 Geometry 1. 4 Perimeter, Area 21