Download angle measures in polygons

Angle Measures in Polygons
Objectives:
…to determine the total number of degrees in the interior angles of a
polygon
...to determine the measurement of an interior angle of a regular polygon
...to determine the number of sides of a polygon given the total number of
degrees in the interior angles
Assessment Anchor:
8.B.2.1 – Determine the measurement of a missing side(s) or angle(s) in
a polygon
Vocabulary alert!!
POLYGON – a closed 2-dimensional figure formed by the
intersection of 3 or more line segments
REGULAR POLYGON – a polygon with all sides and all
angles congruent
Name of Polygon
Number of Sides
Triangle
Quadrilateral
3
4
5
6
7
8
9
10
N – gon
N
Total Interior Angle Measure
(Formula Sheet)
Angle Measures in Polygons
EXAMPLES
1)
Determine the measure of the missing angle in the triangle:
31°
2)
total----------------->
so far:--------------->
missing angle:----->
In a quadrilateral, each of two angles has a measure of 115°. If the measure
of the third angle is 70°, what is the measure of the remaining angle?
(HINT: draw a rough sketch!)
total----------------->
so far:--------------->
missing angle:----->
3)
If the sum of the interior angle measures of a polygon is 2340°, then what
kind of polygon is it? (HINT: use formula!)
polygon:------------>
4)
What is the measure of every interior angle of a regular hexagon?
total----------------->
# angles:------------>
each angle:--------->
5)
Find the measure in degrees of the smallest angle in the triangle.
6x + 4
total?
2x
2x + 6