Angles in polygons

What you'll learn

1. 1

   Imagine a triangle made from 3 lollipop sticks. Each corner is an angle — like a hinge!

2. 2

   How many corners does a triangle have?

3. 3

   Here's a triangle. The 3 angles inside always add up to 180° — like a straight line!

4. 4

   Let's find the missing angle in a triangle!

5. 5

   Use the protractor to measure this angle inside a pentagon.

6. 6

   What do all 3 angles in a triangle add up to?

7. 7

   A quadrilateral (4-sided shape) can be split into 2 triangles. What do its 4 angles add to?