2. Geom10.7.notebook March 19, 2012
10.7 Inscribed and Circumscribed Polygons
A polygon is INSCRIBED IN a circle if all of its vertices lie
on the circle.
incenter
2
3. Geom10.7.notebook March 19, 2012
A polygon is CIRCUMSCRIBED ABOUT a circle if each of its sides is tangent to
the circle.
circumcenter
incenter
Theorem: If a quadrilateral is inscribed in a circle, then
its opposite angles are supplementary.
B
A
C
D
3
4. Geom10.7.notebook March 19, 2012
Theorem: If a parallelogram is inscribed in
a circle, then it must be a rectangle.
EXIT SLIP:
Find all unknown angle measures and arc measures
J
80o
90o
M
20o
K
L
4
