1. WARM UP Find the following measures.

2. Section 9.4 Relationships between Arcs and Chords

3. CHORDS Remember diameters are also chords. By definition a chord is a segment that has two end points on the circle.

4. CHORDS and ARCS What is true about chords and the arcs they make? What is x? Congruent chords make congruent arcs 10 158 o xoxo

5. ARCS and CHORDS What happens if you know the arcs? What is y? Congruent arcs make congruent chords y 16.5 142.87 o 16.5

6. Diameters and Chords A diameter that is perpendicular to a chord bisects the chord and its arc. Find the measure of x and the measure of each arc. x 12.5 127 o 12.5 63.5 o 116.5 o

7. Same circles or Congruent circles Congruent chords are equally distant from the center x 11 4 y x = 4 y = 11

8. Find the missing values. z z = 13 – 5 because it’s a radius z = 8 13 y = 12 because its equal to x. x = 12 because it’s a Pythagorean Triple.

9. o o Find the missing values. 60 o 30 o 60 o 30 o 6 Use a 30-60-90 triangle to solve for the missing legs. 3 = 3 60 o 120 o

10. Find the missing values. o o 105 o 8 16

11. QUIZ 9.1 Circle Terms 9.2 Tangents 9.3 Arcs and Central Angles 9.4 Chords and Arcs

12. Practice Problems Page 346 Classroom Exercises #4, 5 Page 347 Written Exercises #10 – 13