1. Splash Screen

2. Example 2 Use Area of Circles to Solve Problems PICTURE FRAMES The rectangular matting for a picture frame has a circular cutout for the photograph, as shown in the figure. What is the area of the mat? Round to the nearest tenth.

3. Example 2 Use Area of Circles to Solve Problems Answer: The area is about 165.7 sq. in. Find the area of the rectangle minus the area of the circle. Area of rectangle Area of circle A=ℓw –  r 2 =18 ● 12 –  ● 4 2 Replace ℓ with 18, w with 12, and r with 4. =216 – 16  Simplify.  165.7Use a calculator.

4. Example 2 CYP A.150.6 in 2 B.131.7 in 2 C.124.6 in 2 D.79 in 2 The rectangular matting for a picture frame has a circular cutout as shown in the figure. What is the approximate area of the matting?

5. Concept B Sector – a pie-shaped part of a circle bound by the radius of a circle and an arc Central angle – an angle whose vertex is the center of a circle and whose sides intersect the circle

6. Example 3 Find the Area of a Sector Find the area of the shaded sector in the circle. Round to the nearest tenth. Area of a sector Answer: The area is about 37.7 m 2. Replace N with 120 and r with 6. Simplify. Use a calculator.

7. Example 3 CYP A.4.2 in 2 B.16.8 in 2 C.33.5 in 2 D.66.0 in 2 To the nearest tenth, what is the area of the shaded sector in the circle?

8. Concept B