Proofs In Plane Geometry
Properties Of Circles
1. tan.
rad.
2. rt.
in semicircle
3.
s in same seg.
4.
at centre = 2
at circ.
5.
s in opp. seg. (
)
6. tan. from ext. pt.

2. rt.

3.

4.


5.


6. tan. from ext. pt.
Congruent & Similar Triangles
Midpoint Theorem
If
and
are the midpoints of
and
respectively, then
//
and
.







Tangent-Chord Theorem (Alternate Segment Theorem)
If
is a tangent to the circle at
, then
and
.



