Presentation on theme: "Warm up ♥2 – 18 evens only. ♥This will be graded in 10 minutes. 2.2.79 4.27.93 6.61.78 8.138.4 10. 7.16 12. 309.4° 14.107 ° 16.1.6 ° 18.72.5 °"— Presentation transcript:
Warm up ♥2 – 18 evens only. ♥This will be graded in 10 minutes ° ° ° °
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 =
Let’s Practice I need 2 volunteers to hand out whiteboards and markers.