Angles in Lines, Triangles and Polygons

Angles in Lines

100

What are supplementary angles?

Angles that add up to 180 degrees.

200

What are complementary angles?

Angles that add up to 90 degrees.

300

What are corresponding angles?

Angles that are on the same side of the transversal, are equal and are at the same spot.

400

What are alternate interior angles?

Angles that are equal, are inside the parallel lines and are opposite each other.

500

What are alternate exterior angles?

Angles that are outside the parallel lines, are equal and are opposite each other.

Interior Angles in Triangles

100

What is the interior angle sum of a triangle?

180 degrees.

200

Two interior angles in a triangle are 40 and 50 degrees. What is the third angle?

90 degrees

300

The sum of the interior angles of a pentagon

540

400

Two interior angles in a triangle are 55 and 120 degrees. What is the third angle?

5 degrees

500

The sum of the interior angles of an octagon

1080

Name the Shape

100

5 sided shape

Pentagon

200

6 sided shape

hexagon

300

7 sided shape

heptagon

400

8 sided shape

octagon

500

10 sided shape

decagon

Interior Angles in Polygons

100

What is the formula to find the interior angle sum of any polygon?

S = (n-2)180

200

 find one interior angle of a square

90

300

Find ONE interior angle of a regular octagon.

135 degrees

400

Find the measure of one interior angle in a regular 20-gon.

162 degrees

500

Find the interior angle sum of a regular 25-gon.

4140 degrees

Exterior Angles in Polygons

100

What is the exterior angle sum of any polygon?

360 degrees

200

How do I find the measure of ONE exterior angle of any regular polygon?

Divide 360 by the number of sides.

300

Find the exterior angle sum of a pentagon.

360 degrees

400

Find the measure of ONE exterior angle of a 15-gon.

24 degrees

500

Quadrilateral ABCD has exterior angles 110, 50, 120, and x degrees. Find the missing exterior angle measure.

80 degrees