10.3 Warmup Find the value of x given that C is the center of the circle and that the circle has a diameter of 12. November 24, 2018 Geometry 10.3 Using Chords
10.3 Warmup Factor Completely 𝟓 𝒙 𝟐 −𝟑𝟓𝒙 2. 𝟔 𝒙 𝟐 +𝟏𝟐𝒙+𝟔 𝟓 𝒙 𝟐 −𝟑𝟓𝒙 2. 𝟔 𝒙 𝟐 +𝟏𝟐𝒙+𝟔 𝒙 𝟐 +𝟏𝟏𝒙+𝟐𝟒 4. 𝒙 𝟐 −𝟔𝒙+𝟗 5. 𝒙 𝟐 −𝟒𝒙−𝟓 6. 𝒙 𝟐 −𝟗 November 24, 2018 Geometry 10.3 Using Chords
10.3 Warmup (Answers) Factor Completely 𝟓 𝒙 𝟐 −𝟑𝟓𝒙 2. 𝟔 𝒙 𝟐 +𝟏𝟐𝒙+𝟔 𝟓 𝒙 𝟐 −𝟑𝟓𝒙 2. 𝟔 𝒙 𝟐 +𝟏𝟐𝒙+𝟔 𝒙 𝟐 +𝟏𝟏𝒙+𝟐𝟒 4. 𝒙 𝟐 −𝟔𝒙+𝟗 5. 𝒙 𝟐 −𝟒𝒙−𝟓 6. 𝒙 𝟐 −𝟗 5𝑥(𝑥−7 6(𝑥+1)(𝑥+1 𝑥+8)(𝑥+3 𝑥−3)(𝑥−3 𝑥−5)(𝑥+1 𝑥−3)(𝑥+3 November 24, 2018 Geometry 10.3 Using Chords
Geometry 10.3 Using Chords mbhaub@mpsaz.org
10.3 Essential Question In a circle, what is true when a radius is perpendicular to a chord? November 24, 2018 Geometry 10.3 Using Chords
Goals Compute arc measures and angle measures November 24, 2018 Geometry 10.3 Using Chords
Arc Theorems November 24, 2018 Geometry 10.3 Using Chords
Congruent Corresponding Chords Theorem (Thm 10.6) In the same circle, or in congruent circles, two minor arcs are congruent if and only if corresponding chords are congruent. November 24, 2018 Geometry 10.3 Using Chords
Theorem 10.6 B A C D November 24, 2018 Geometry 10.3 Using Chords
Example 1 Solve for x. 5x + 10 = 120 5x = 110 x = 22 (5x + 10) 120 November 24, 2018 Geometry 10.3 Using Chords
Example 2 x 𝑥+𝑥+150=360 2𝑥+150=360 150 ͦ 2𝑥 =210 𝑥=105 x =105° November 24, 2018 Geometry 10.3 Using Chords
Perpendicular Chord Bisector Theorem (Thm 10.7) If a diameter is perpendicular to a chord, then it bisects the chord and the subtended arc. November 24, 2018 Geometry 10.3 Using Chords
Example 3 Solve for x. 2x = 52 x = 26 52 2x November 24, 2018 Geometry 10.3 Using Chords
Example 4 𝐶𝐸=5+5=10 9𝑥=80−𝑥 10𝑥=80 𝑥=8 =2∙9 8 =144° a. Find the length of 𝐶𝐸 . b. Find . 𝐶𝐸=5+5=10 9𝑥=80−𝑥 10𝑥=80 𝑥=8 =2∙9 8 =144° November 24, 2018 Geometry 10.3 Using Chords
Perpendicular Chord Bisector Converse Theorem (Thm 10.8) If a chord is the perpendicular bisector of another chord, then it is a diameter. Diameter November 24, 2018 Geometry 10.3 Using Chords
Equidistant Chords Theorem (Thm 10.9) Two chords are congruent if and only if they are equidistant from the center of a circle. November 24, 2018 Geometry 10.3 Using Chords
The red wires are the same length because they are the same distance from the center of the grate. November 24, 2018 Geometry 10.3 Using Chords
Example 5 Solve for x. 16 4x – 2 = 16 4x = 18 x = 18/4 x = 4.5 4x – 2 November 24, 2018 Geometry 10.3 Using Chords
Example 6 In the diagram, QR = ST = 16, CU = 2x, and CV = 5x − 9. Find the length of the radius of ⊙C. November 24, 2018 Geometry 10.3 Using Chords
Your Turn In the diagram, JK = LM = 24, NP = 3x, and NQ = 7x − 12. Find the radius of ⊙N. November 24, 2018 Geometry 10.3 Using Chords
Summary Congruent chords subtend congruent arcs and are equidistant from the center of the circle. If a diameter is perpendicular to a chord, then it bisects it. November 24, 2018 Geometry 10.3 Using Chords
Homework mbhaub@mpsaz.org November 24, 2018 Geometry 10.3 Using Chords