CK-12 Geometry - Second Edition

9.1. Parts of Circles & Tangent Lines http://www.ck12.org

31. Circles tangent atTare centered atMandN.STis tangent to both circles atT. Find the radius of the smaller
    circle ifSN⊥SM,SM= 22 ,T N=25 andm^6 SNT= 40 ◦.


32. Four circles are arranged inside an equilateral triangle as shown. If the triangle has sides equal to 16 cm, what
    is the radius of the bigger circle? What are the radii of the smaller circles?


33. Circles centered atAandBare tangent atW. Explain whyA,BandWare collinear.T Uis a common external
    tangent to the two circles.V Wis tangent to both circles. Justify the fact thatT V∼=V U∼=V W.

Review Queue Answers

1.y=− 2 x+ 3

2.y=^13 x

3.y=− 3 x− 13