10.3 Lesson: Circles and Tangents

Q is the center of this triangle.

a) Name the circle:

b) Name a radius shown:

c) What is the length of the radius?

d) What is the length of the diameter?

e) Name all interior points shown:

f) Name all exterior points shown:

Q is the center of this triangle.
a) Circle Q
b)  $\overline{QP},\ \overline{QT}$  
c) r = 16 m
d) d = 32 m
e) Interior Points: Points R, Q, and S
f) Exterior Points: X

Name Examples of each.

a) Center:

b) All Radii:

c) All Chords:

d) All Secants:

e) Diameter:

f) Tangent:

g) Point of Tangency:

h) Interior Points:

i) Exterior Points

a) Point O
b)  $\overline{ON},\ \overline{OR},\ and\ \overline{OM}$  
c)  $\overline{MN}\ and\ \overline{MT}$  
d)  $\overleftarrow{M}\overrightarrow{T}$  
e)  $\overline{MN}$  
f)  $\overleftarrow{P}\overrightarrow{S}$  
g) Point Q
h) Interior Points: B, I and O
i) Exterior Points: P and S

 $\Delta TRW$  is circumscribed about Circle A. The perimeter of  $\Delta TRW$  is 50, TK = 3, and WM = 9.5. our goal is to find the length of TR.

By the External Tangent Congruence Theorem, since TK = 3, we know that TL = 3 also.

Likewise, WK = WM and RL = RM.