1. 1. 3x=x+50 2. y+5y+66=360 3. x+14x=180 4. a 2 +16=25 Note: A diameter is a chord but not all chords are diameters

3.  An arc is a portion of the circumference of a circle.  A chord is a line segment drawn between the end points of the arc chord major arc minor arc

4.  central angle: in degrees  the length of the arc: in radians

5. B central angle minor arcs AC CB minor arcs AC CB Major arcs ABC CAB Major arcs ABC CAB Semicircle ACB Semicircle ACB center diameter chord radius A C O

6.  The measure of an arc formed by two adjacent arcs is the sum of the measures of the two arcs. mABC = mAB + mBC

7.  If the same circle, or in congruent circles, two minor arcs are congruent if and only if their corresponding chords are congruent.

8. 1. 2. yes No Arcs AB and CD Arcs XY and ZW

9.  If a diameter of a circle is perpendicular to a chord, then the diameter bisects the chord and its arc.

10.  If one chord is a perpendicular bisector of another chord, then the first chord is a diameter.

11.  In the same circle, or in congruent circles, two chords are congruent iff they are equidistant from the center.

12.  Find the measure of each arc of A. a) BD b) BE c) BED 125 0 137 0 235 0

13. 122 0 How to locate the center of the following circle using the chords shown.

15. Find the measurement of the central angle representing each category. List them from least to greatest. 25.2 0,32.4 0, 75.6 0, 93.6 0, 133,2 0

16.  ≈14.66 cm