Geometry
Notes – Lesson 10.3, 10.5
Name __________________________
To find the measurement of a central angle ___________  ___________________________________
Find the measurements of the central angles.
1.
2.
3.
The radius is the distance from the center to a ________________.
The apothem is the perpendicular distance from the center to a _______________.
Each regular polygon has radii and an apothem as shown. Find the measure of each numbered angle.
4.
5.
6.
Area of a REGULAR Polygon
Formula: _________________
Examples: Given apothem and side.
7.
where a = _______________ and
8.
p = ______________________
9. A nonagon, a = 16.5 in., s = 10 in.
Examples: Using special right triangle rules.
10.
11.
12
Examples: Using trigonometry rules.
13.
14.
15. Regular hexagon with apothem of 18 in.
16. regular octagon with radius of 20 cm.
17. a triangular dog pen with apothem 4 m
18.
19. a regular decagon with apothem 10 in.
20. a octagonal floor of a gazebo with apothem 6 ft.