Warm up 2 – 18 evens only. This will be graded in 10 minutes. 2.79 27.93 61.78 138.4 7.16 309.4° 107 ° 16. 1.6 ° 18. 72.5 °

9.2 Tangents and Secants Tangents and secants are LINES. A tangent line intersects the circle at exactly ONE point. A secant line intersects the circle at exactly TWO points.

A little extra information The word tangent comes from the Latin word meaning to touch The word secant comes from the Latin word meaning to cut.

Important Theorems Tangent Theorem: If a line is tangent to a circle, then the line is perpendicular to a radius of the circle drawn to the point of tangency. The line AB is tangent to circle C at B. How could we prove that segment CB and line AB are perpendicular?

Converse of the Tangent Theorem Go waaaayyy back… how do we get a converse statement? What would be the Converse of the Tangent Theorem? If a line is perpendicular to a radius of a circle at its endpoint on the circle, then the line is tangent to the circle.

Radius and Chord Theorem A radius that is perpendicular to the chord of a circle bisects the chord. QR = 3 What is the measure of RS? XR = 7 and WR = 2 Find the missing measures of the remaining segments. RZ = RY = XW = WZ = XZ = 7 6.7 13.4

I need 2 volunteers to hand out whiteboards and markers. Let’s Practice I need 2 volunteers to hand out whiteboards and markers.

Your assignment Pg 577; 10-13, 19-26 Pg 846, Lesson 9.2, 1-6