Copyright © Cengage Learning. All rights reserved.

Slides:



Advertisements
Similar presentations
Area of Polygons and Circles
Advertisements

Geometry Sector Area and Arc Length
Areas of Circles, Sectors and Segments Lesson 11.6
Area of Circles and Sectors Lesson 7.4A M.3.G.1 Calculate probabilities arising in geometric contexts (Ex. Find the probability of hitting a particular.
Distance around the circle 2  r = C or d  = C.
105  32   16  36.5  105  Warm-up Find the measures of angles 1 – 4.
Chapter Circle  A set of all points equidistant from the center.
Warm up: Solve for x 1.) 2.) 4.) 3.) 124◦ 70◦ x 18◦ x 260◦ x 20◦ 110◦
Chapter 10: Area 10.7 Areas of Circles & Sectors.
7.2 – Sectors of Circles Essential Question: How do you find the radius of a sector given its’ area and arc length?
Warm up. 2 Types of Answers Rounded Type the Pi button on your calculator Toggle your answer Do NOT write Pi in your answer Exact Pi will be in your.
Warm-Up 1.Find the circumference of a circle with a diameter of 10ft. Round your answer to the nearest tenth. 2.Find the circumference of  A if the radius.
Radian Measure Advanced Geometry Circles Lesson 4.
Copyright © Cengage Learning. All rights reserved. 12 Geometry.
Holt McDougal Geometry 11-3 Sector Area and Arc Length Toolbox Pg. 767 (12-20; 33 why 4 )
Section 11-3 Sector Area and Arc Length. The area of a sector is a fraction of the circle containing the sector. To find the area of a sector whose central.
Copyright © Cengage Learning. All rights reserved.
10.6/10.7 Circles, Arcs, Segments, and Sectors
Objectives Find the area of sectors. Find arc lengths.
Area of a circle.
Warm up: Solve for x 1.) 2.) 4.) 3.) 124◦ 70◦ x 18◦ x 260◦ x 20◦ 110◦
Area of Circles Chapter 7B.
Arcs, Sectors & Segments
10.7 Areas of Circles and Sectors
11.6 Areas of Circles, Sectors, and Segments
7-7 Areas of Circles and Sectors
Section 11.3 Notes: Areas of Circles and Sectors
Practice Quiz Circles.
Circles.
Sector Area and Arc Length
Circumference, Arc Length, Area, and Area of Sectors
Copyright © 2014 Pearson Education, Inc.
Notes 6-1: Radian Measure
EOC REVIEW Question of the Day.
11.3 Areas of Circles and Sectors
Proportions in Circles
2 Types of Answers Exact Rounded Use the Pi button on your calculator
Circumference, Arc Length, Area, and Area of Sectors
Measurement of Solids & Figures
Warm-Up A circle has a diameter of 10 in. What is the arc length in radians of a sector with 135°? What is the arc length in radians of a sector with 95°?
12.3 Sector Area and Arc Length
Warm UP! Circle O has a radius of 20 feet. What is the length of arc KL? K 65o O L 20 ft.
11.3 Sector Area and Arc Length (Part 1)
Section 7.5 More Area Relationships in the Circle
12-2 Arcs and Chords.
End of 10.6 and All of 10.7.
12.3 Sector Area and Arc Length
Objectives Find the area of sectors..
Choose a shape and write down everything you know about it.
Objective Apply formulas for perimeter, area, and circumference.
Warm up: Solve for x 1.) 2.) 4.) 3.) 124◦ 70◦ x 18◦ x 260◦ x 20◦ 110◦
Section 7.6: Circles and Arcs
Warm Up: Do at the beginning of 12.3 notes
ANSWERS WILL BE IN SQUARE UNITS
Arc Length and Sector Area
Copyright © Cengage Learning. All rights reserved.
Unit 4: Circles and Volume
Copyright © Cengage Learning. All rights reserved.
Finding Arc Lengths and Areas of Sectors
Unit 4: Circles and Volume
Sector Area and Arc Length
L.T. 11.3: Find the area of sectors
Areas of Circles, Sectors and Segments Lesson 11.6
Areas of Plane Figures 11-6 Arc Lengths and Areas of Sectors
Copyright © Cengage Learning. All rights reserved.
Warm up: Solve for x 1.) 2.) 4.) 3.) 124◦ 70◦ x 18◦ x 260◦ x 20◦ 110◦
Warm up: Solve for x 1.) 2.) 4.) 3.) 124◦ 70◦ x 18◦ x 260◦ x 20◦ 110◦
Circle Review Bingo The solutions are linked. Click on the answer on the next slide and it will jump you to the slide that is the question to the solution.
Presentation transcript:

Copyright © Cengage Learning. All rights reserved. 8 Locus and Concurrence Chapter Copyright © Cengage Learning. All rights reserved.

More Area Relationships in the Circle 8.5 Copyright © Cengage Learning. All rights reserved.

More Area Relationships in the circle Definition A sector of a circle is a region bounded by two radii of the circle and an arc intercepted by those radii. (See Figure 8.47.) Figure 8.47

AREA OF A SECTOR

Area of a Sector Postulate 23 The ratio of the degree measure m of the arc (or central angle) of a sector to 360° is the same as the ratio of the area of the sector to the area of the circle; that is, Theorem 8.5.1 In a circle of radius r, the area A of a sector whose arc has degree measure m is

Example 1 If m O = 100°, find the area of the 100° sector shown in Figure 8.49. Use your calculator and round the answer to the nearest hundredth of a square inch. Figure 8.49

Example 1 – Solution becomes  87.27 in2

Area of a Sector In applications with circles, we often seek exact answers for circumference and area; in such cases, we simply leave  in the result. For instance, in a circle of radius length 5 in., the exact circumference is 10 in. and the exact area is expressed as 25 in².

Area of a Sector Because a sector is bounded by two radii and an arc, the perimeter of a sector is the sum of the lengths of the two radii and the length of its arc. Corollary 8.5.2 The area of a semicircular region of radius length r is A =  r 2.

AREA OF A SEGMENT

Area of a Segment Definition A segment of a circle is a region bounded by a chord and its minor (or major) arc. In Figure 8.51, the segment is bounded by chord and its minor arc . Figure 8.51

Example 4 Find the exact area of the segment bounded by the chord and the arc whose measure is 90°. The radius has length 12 in., as shown in Figure 8.52. Figure 8.52

Example 4 – Solution Let represent the area of the triangle shown. Because A∆ + Asegment = Asector we see that Asegment = Asector – A∆ = 122 –  12  12 =  144 –  144 = (36 – 72) in2

Area of a Segment In Example 4, the boundaries of the segment shown are chord and minor arc . Therefore, the perimeter of the segment is given by Psegment = AB + ℓ