7.1 and 7.2.notebook
1
October 29, 2015
Today:• Go over quizzes-grab your folder from the front table. • Review for Test
~Main portion tomorrow, big figure Monday• Notes on 7.1, 7.2, 7.3• HW: 6.7 and 7.1
7.1 and 7.2.notebook
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October 29, 2015
CirclesLesson 7.1
Objectives: • To define a circle and related figures• To identify the parts of a circle
Circle The set of all points in a plane at a given distance from a point.
Radius A segment from a point on a circle or sphere to the center.
(OP is a radiusplural of radius is radii)
Center Center of circle is usually O.
O
P
7.1 and 7.2.notebook
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October 29, 2015
Congruent Circles Circles with the same radius
Concentric Circles Circles with the same center
• Arc of a circle Two points on a circle and the continuous part of the circle between two points.
• Semicircle An arc that makes up half of the circle.
• Minor arc An arc that is smaller than a semicircle.
• Major arc An arc that is larger than a semicircle.
7.1 and 7.2.notebook
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October 29, 2015
This is how we label arcs.
B C
A
Notice it has two letters Notice it has three letters
Notice it has three letters
• Chord of a circle A line segment whose endpoints lie on a circle
• Diameter A chord that passes through the center of a circle
O
P
Diameter
Chord
7.1 and 7.2.notebook
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October 29, 2015
• Secant A line that contains a chord.
• Tangent A line that lies in the plane of a circle and that intersects the circle at exactly one point.
Secant
Tangent
• Inscribed angle An angle whose vertex lies on a circle and whose sides contain chords of the circle.
• Central angle An angle whose vertex is the center of a circle and whose sides contain radii of the circle.
Central Angle
Inscribed Angle
7.1 and 7.2.notebook
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October 29, 2015
What does this picture best describe?
• A) Tangent• B) Radius • C) Secant• D) Diameter• E) Center• F) Chord
What does this picture best describe?
• A) Tangent• B) Radius • C) Secant• D) Diameter• E) Center• F) Chord
7.1 and 7.2.notebook
7
October 29, 2015
What does this picture best describe?
• A) Tangent• B) Radius • C) Secant• D) Diameter• E) Center• F) Chord
What does this picture best describe?
• A) Tangent• B) Radius • C) Secant• D) Diameter• E) Center• F) Chord
7.1 and 7.2.notebook
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October 29, 2015
What does this picture best describe?
• A) Concentric Circles• B) Congruent Circles• C) Major arc• D) Minor arc• E) Semicircle• F) Angles
What is the term for ?
• A) Concentric Circles• B) Congruent Circles• C) Major arc• D) Minor arc• E) Semicircle• F) Angles
A
B
C
7.1 and 7.2.notebook
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October 29, 2015
What is the term for ?
• A) Concentric Circles• B) Congruent Circles• C) Major arc• D) Minor arc• E) Semicircle• F) Angles
A
B
C
Lesson 7.2Discovering Chord Properties
Objectives:• To discover the properties of chords of circles• To develop problem solving skills
7.1 and 7.2.notebook
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October 29, 2015
The measure of an intercepted arc is the measure of it's central angle.
• C61 If two chords in a circle are congruent, then they determine two central angles that are congruent.
Central Angle
Central Angle
7.1 and 7.2.notebook
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October 29, 2015
• C62 If two chords in a circle are congruent, then their intercepted arcs are congruent.
• C63 The perpendicular from the center of a circle to a chord is the perpendicular bisector of the chord.
7.1 and 7.2.notebook
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October 29, 2015
• C64 Two congruent chords in a circle are equally distant from the center of the circle.
• C65 The perpendicular bisector of a chord passes through the center of the circle.
7.1 and 7.2.notebook
13
October 29, 2015
If arc AB = 145o , find the value of angle x.
145o
xA
B
O
Find the value of x
7.1 and 7.2.notebook
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October 29, 2015
Find the value of x.
If AB = 10 cm, find the length of AM.
7.1 and 7.2.notebook
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October 29, 2015
If arc ACB = 215o , find the value of angle x.
215o
x
A
B
O
C
Homework for Friday
6.7pg. 319
1-19, 21, 27-30, 387.1
p. 3311-14, 19-21(sketch these), 24-26
(graph paper)
Homework for Monday
7.2p. 335
1-6, 10, 11, 16-18, 207.3
p. 3401-6, 8-10, 18, 20, 21
![Alpha Decay basics [Sec. 7.1/7.2/8.2/8.3 Dunlap].](https://static.documents.pub/doc/80x56/56649ede5503460f94bee9e9/alpha-decay-basics-sec-71728283-dunlap.jpg)
