IXL - Interior and exterior angles of polygons: mixed practice (Geometry practice)

The diagram shows a convex polygon.

What is the sum of the exterior angle measures, one at each vertex, of this polygon?

ref_doc_title.

Learn with an example

question

The diagram shows a convex polygon.

What is the sum of the interior angle measures of this polygon?

key idea

The sum of the interior angle measures of a triangle is 180°.

solution

Look at this convex polygon.

To find out how many triangles make up this polygon, pick a vertex and draw all the diagonals from that vertex.

This polygon is made up of 8 triangles. Since the sum of the interior angle measures of each triangle is 180°, the sum of the interior angle measures of this polygon is

180°

1,440°

Notice that this polygon has 10 sides and is made up of 8 triangles. In general, if a convex polygon has

sides it is made up of

(

–

)

triangles.

In other words, the sum of the interior angle measures of a convex polygon with

sides is

(

–

)

180°

Looking for more? Try this:

$Confetti$

Excellent!

Now entering the Challenge Zone—are you ready?

Questions
answeredQuestions

Time
elapsedTime

hr	min	sec
00	00	06

SmartScore
out of 100
IXL's SmartScore is a dynamic measure of progress towards mastery, rather than a percentage grade. It tracks your skill level as you tackle progressively more difficult questions. Consistently answer questions correctly to reach excellence (90), or conquer the Challenge Zone to achieve mastery (100)! Learn more

Teacher tools

Work it out

Not feeling ready yet? These can help:

G.3Exterior angles of polygons

G.2Interior angles of polygons

Excellent! You got that right!

Jumping to level 1 of 1

Excellent!