Name the term that best describes the notation.

Secant

Radius

DiameterChord

Tangent

TANGENT = a LINE that

intersects the circle exactly

ONE time

Common Tangents

http://www.ies.co.jp/math/java/geo/comtan/comtan.html

YOUR TURN

3 common tangents 0 common tangents 1 common tangent

If a line is tangent to a circle, then it is perpendicular to the radius drawn to the point of tangency

Point of Tangency

More Pythagorean Theorem type problems! Yeah!!

leg2 + leg2 = hyp2

x = 15

92 + 122 = x2

leg2 + leg2 = hyp2

RQ = 16

122 + x2 = (8+12)2

122 + x2 = 202

leg2 + leg2 = hyp2

r2 + 482 = (r+36)2

r2 + 2304 = r2 +72r+1296

r=14

RS

T

TSRS

If two segments from the same

exterior point are tangent to a circle,

then they are congruent.

Party hat problems!

R

S

T

22 x

11 1122 x92 x

3x

A

C

B

132 x

47

30x

2 13 47x

A

C

B

15

2x

9

28x

15 9

2x