Practice. Area of Irregular Figures. Estimate the area of each figure. Each square represents 1 square foot. Choose the letter for the best answer. 1.

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1 Name Date Class Practice Estimate the area of each figure. Each square represents 1 square foot. Choose the letter for the best answer A 11 ft 2 C 15 ft 2 B 14 ft 2 A 24 ft 2 C 32 ft 2 B 26 ft 2 Find the area of each figure. Use 3.14 for π. The first one is done for you ft The figure shows the dimensions of a room. How much carpet is needed to cover the floor? 207 Holt McDougal Mathematics

2 Name Date Class Practice B Estimate the area of each figure. Each square represents 1 square foot _ Find the area of each figure. Use 3.14 for π Marci is going to use tile to cover her terrace. How much tile does she need? 209 Holt McDougal Mathematics

3 Name Date Class Practice C Estimate the area of each figure. Each square represents 1 square foot _ Find the area of each figure. Use 3.14 for π The figure shows the dimensions of a room in which wedding receptions are held. The room is being carpeted. The three semi-circular parts of the room are congruent. How much carpet is needed? 7. A polygon has vertices at F( 5, 2), G( 3, 2), H( 3, 4), J(1, 4), K(1, 1), L(4, 1), M(4, 2), N(6, 2), P(6, 3), and Q( 5, 3). Graph the figure on the coordinate plane. Then find the area and the perimeter of the figure. 210 Holt McDougal Mathematics

4 Name Date Class Problem Solving Write the correct answer. 1. Explain how to find the area of the composite figure below. Then find the area. 2. Mr. Bemis carpets the living room shown below. If he pays $20 per square meter, what is the total cost of the carpet? Solution: The irregular figure is made up of a rectangle and a triangle. Find the area of each, and add to find the area of the figure. The area of the rectangle is = 250 ft 2. Subtract 10 from the length of the long side, 25, to find the height of the triangle: = 15. The bottom of the rectangle is 10 ft. Subtract that from the length of the base of the figure, 20, to find the base of the triangle: = 10. Find the area of the triangle: = 75 Add the two areas: = 325. Divide the living room into two rectangles. The dimensions of the two rectangles are 5 m by m and 3 m by m. Find the area of each rectangle. 5 = 3 = Add the areas. + =. Multiply the total area by the cost of carpet per square meter. 20 =. The total cost of the carpet is $. The area of the figure is 325 square feet. Choose the letter of the correct answer. 3. Norene builds the deck at the right. What is the area of the deck? A 86 m 2 C 66 m 2 B 76 m Holt McDougal Mathematics

5 Name Date Class Reading Strategies Draw a Picture A composite figure is made of shapes that you know, such as rectangles, triangles, or semi-circles. You can draw a line to break a composite figure into other shapes. Then you can use those shapes to help you find the area. Answer each question. 1. A dashed line has been drawn through the figure. What two shapes does the dashed line create? 2. How can you find the area of the rectangle? 3. What is the area of the rectangle? 4. How can you find the area of the right triangle? 5. What is the area of the right triangle? 6. How can you use the area of the rectangle and the area of the right triangle to find the total area of the composite figure? 7. What is the total area of the composite figure? 55 Holt McDougal Mathematics

6 Name Date Class Puzzles, Twisters & Teasers What s Bugging You? Each square represents 1 square foot. Estimate the area of each irregular figure. Circle the letter next to the better estimate D 24 ft 2 I 26 ft 2 F 11 ft 2 N 15 ft 2 Next, find the area of each composite figure. Use 3.14 for π. Circle the letter next to your answer L 38 m 2 R 42 m 2 7. A ft 2 E ft 2 8. O 160 m 2 E 168 m 2 H 52 m 2 L 60 m 2 S ft 2 Y ft 2 F 126 m 2 B 144 m 2 Write the circled letters above the problem numbers to solve the riddle. What kind of insect breathes fire? A G Holt McDougal Mathematics