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This PowerPoint presentation explores the relationship between chords, secants, and tangents in circles, focusing on vertical angles and arc measures. It discusses how intersecting chords create vertical angles that are congruent, examines the angles formed by secants with arcs, and explains the relationship between tangent lines and angles. The presentation includes illustrations, angle measurements, and interactive components to enhance understanding of circular geometry concepts. Ideal for students seeking to grasp the fundamental principles of angles and arcs within circles.
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Other Angle Relationships In Circles Geometry Chapter 10 A BowerPoint Presentation
2 chords • Draw 2 intersecting chords in your circle • Label a pair of vertical angles as angles 1 and 2 • What do you know about angles 1 and 2?
2 chords • Draw 2 intersecting chords in your circle • Label a pair of vertical angles as angles 1 and 2 • What do you know about angles 1 and 2? • They are congruent!
2 chords • Angles 1 and 2 intercept two different arcs of the circle. Do these arcs have to be congruent?
2 chords • Angles 1 and 2 intercept two different arcs of the circle. Do these arcs have to be congruent? • No!
2 chords • Find the measures of angles 1 & 2
2 chords • Find the measures of angles 1 & 2 Both angles = 110o
2 chords • Find x
2 chords • Find x x = 80
2 secants • Put a point outside the circle (probably to the right) • Draw two secants that go through that point and through the circle • Do you see how the angle you’ve created intercepts two arcs in the circle?
2 secants • Find the measure of angle 1
2 secants • Find the measure of angle 1 Angle 1 = 50o
2 secants • Find x
2 secants • Find x x = 130
1 secant & 1 tangent • Put a point outside the circle (probably to the right) • Draw a secant that goes through the circle and through the point • Draw a tangent that touches the circle at one point and goes through your point • Do you see how the angle you’ve created intercepts two arcs in the circle?
1 tangent & 1 secant • Find the measure of angle 1
1 tangent & 1 secant • Find the measure of angle 1 Angle 1 = 45o
1 secant & 1 tangent • Find x
1 secant & 1 tangent • Find x x = 90
2 tangents • Put a point outside the circle (probably to the right) • Draw two tangents that each touch the circle once and intersect at your point • Do you see how the angle you’ve created intercepts two arcs in the circle?
2 tangents • Find the measure of angle 1 (There is enough information!)
2 tangents • Find the measure of angle 1 (There is enough information – how big is green arc?)
2 tangents • Find the measure of angle 1 Angle 1 = 80o
2 tangents • Find x
2 tangents • Find x x– (360 – x)= 2 (50)
2 tangents • Find x x = 230