1. GEOMETRY HELP Because the diameters are in different units, convert 1 ft to 12 in. The radius of the archery target is 1 ft = 12 in. The area of the archery target is r 2 = (12) 2 = 144 in. 2 A circular archery target has a 2-ft diameter. It is yellow except for a red bull’s-eye at the center with a 6-in. diameter. Find the area of the yellow region. Round your answer to the nearest whole number. Find the areas of the archery target and the bull’s-eye. The radius of the archery target is = 1 ft. 2222 Areas of Circles and Sectors LESSON 10-7 Additional Examples

2. GEOMETRY HELP The area of the red region is r 2 = (3) 2 = 9 in. 2 The radius of the red region is = 3 in. 6262 (continued) The area of the yellow region is about 424 in. 2 Quick Check Areas of Circles and Sectors LESSON 10-7 Additional Examples area of archery target – area of red region = area of yellow region 144 –9 =135 Use a calculator.135

3. GEOMETRY HELP.. The area of sector ACB is 10 m 2. = 10 = 36 5 18 = (6) 2 100 360 Find the area of sector ACB. Leave your answer in terms of. area of sector ACB = r 2 mAB 360 Areas of Circles and Sectors LESSON 10-7 Additional Examples Quick Check

4. GEOMETRY HELP = (24) 2 Substitute. 120 360 = 576 = 192 Simplify. 1313 area of sector AOB = r 2 Use the formula for area of a sector. mAB 360 Find the area of the shaded segment. Round your answer to the nearest tenth. Step 1: Find the area of sector AOB. Areas of Circles and Sectors LESSON 10-7 Additional Examples

5. GEOMETRY HELP A = bhArea of a triangle A = (24 3 )(12)Substitute 24 for b and 12 for h. A = 144 3Simplify. 1212 1212 AB 2 (continued) Step 2: Find the area of AOB. AOB has base 12 3 ft + 12 3 ft, or 24 3 ft and height 12 ft. Areas of Circles and Sectors LESSON 10-7 Additional Examples You can use a 30°-60°-90° triangle to find the height h of AOB and AB. 24 = 2hhypotenuse = 2 shorter leg 12 = hDivide each side by 2. = 3 12 = 12 3longer leg = 3 shorter leg AB = 24 3Multiply each side by 2.

6. GEOMETRY HELP area of segment = 192 – 144 3 To the nearest tenth, the area of the shaded segment is 353.8 ft 2. Step 3: Subtract the area of AOB from the area of sector AOB to find the area of the segment of the circle. (continued) Areas of Circles and Sectors LESSON 10-7 Additional Examples Quick Check Use a calculator.