10-6 Secants, Tangents, & Angle Measures N#____ 4/18/2014

1. 10-6 Secants, Tangents, & Angle MeasuresN#____ 4/18/2014 SLG : Students will be able to find measures of angles formed by lines intersecting on, in, or outside a circle.

2. Secant – A line in the same plane as a circle that intersects the circle in exactly two points. Each secant contains a chord. The angle formed by 2 secants or chords that intersect at point inside a circle is the average of the arcs intercepted by the angle and its vertical angle. 60 x 80 A

3. The angle formed by a secant and a tangent that intersect at a point of tangency equals half of the arc that it intersects. B M 120 1 D C The angle formed by 2 secants, 1 secant & 1 tangent, or 2 tangents that intersect at point outside a circle equals half the difference of the arcs that are intercepted. x 40 x x O 50 P Q 70 260 190

4. Find x. 88 E2 E1 96 62 x x 76 x E4 E3 95 102 60 x 25

5. Find each measure. E6 E5 x 108 x 250 x E8 E7 x 116 238

6. Find each measure. E10 E9 x 179 71 50 x 75 40 E12 E11 140 141 x 62 x

7. A#____ 4/17/2014 SPWS 10-6 & SWS 10-6