10.7 Areas of Circles and Sectors 2011 - Poudre …...10.7 Areas of Circles and Sectors 2011 5 March...

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10.7 Areas of Circles and Sectors 2011 1 March 08, 2011 Feb 242:16 PM Warmup 1. FInd the circumference 2. Find the measure of Abc 3. Find the length of xy ( ( 4.5 a b c 101 o 7 112 o

Transcript of 10.7 Areas of Circles and Sectors 2011 - Poudre …...10.7 Areas of Circles and Sectors 2011 5 March...

Page 1: 10.7 Areas of Circles and Sectors 2011 - Poudre …...10.7 Areas of Circles and Sectors 2011 5 March 08, 2011 Apr 20 2:32 PM New Vocabulary: SECTOR A sector is a region bounded by

10.7 Areas of Circles and Sectors 2011

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March 08, 2011

Feb 24­2:16 PM

Warm­up1.  FInd the circumference     2.  Find the measure of Abc 3. Find the length of xy

( (

4.5

a

b

c101o7

112o

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March 08, 2011

Apr 21­8:04 AM

Challenge Problem

10 ft

8 ft

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March 08, 2011

Apr 20­12:26 PM

10­7:  Areas of Circles, Sectors, and Segments.

Objective:  Find the area of circles, sectors, and                   segments.

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March 08, 2011

Apr 20­2:29 PM

RefresherHow do you find the circumference of a circle?

How do you find the area of a circle?

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March 08, 2011

Apr 20­2:32 PM

New Vocabulary:  SECTOR

A sector is a region bounded by two radii of a circle.

O

X

Y

The blue shaded region is called sector XOY.

How can we find the area of a sector if we know the measure of      XOY ?

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Apr 21­7:32 AM

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March 08, 2011

Apr 21­7:37 AM

Find the area of sector ZOM.

A circle has a diameter of 20 cm.  What is the area of a sector bounded by a 208o major arc?

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Segment of a circle.

New Vocabulary:  SEGMENT

A part of a circle bounded by an arc and the segment joining its endpoints is a segment of a circle.

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March 08, 2011

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O

A

B

How do we find the area of segment AB given the measure of     AOB and the radius ?

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March 08, 2011

Apr 21­7:56 AM

Area of a segment

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March 08, 2011

Apr 21­7:59 AM

Find the area of segment AB.

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March 08, 2011

Apr 21­8:01 AM

A circle has a radius of 12 cm.  Find the area of the smaller segment of the circle bounded by a 60o arc.

Practice

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March 08, 2011

Apr 21­8:15 AM

Homework

pg 577 # 1, 3, 7­19 even, 23, 26, 30

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March 08, 2011

Mar 8­2:40 PM