Angle Sum of a Triangle
The sum of the three interior angles in a triangle is 180°.
An informal way of proving this statement is to do the following activity:
A formal way of proving this statement is to do the following activity:
An informal way of proving this statement is to do the following activity:
- Draw a large triangle on a piece of paper (use a ruler to make sure your lines are straight)
- Cut out the triangle
- Tear off each of the three corners
- Line the three corners up against your ruler to show that they add to a straight line (180°)
A formal way of proving this statement is to do the following activity:
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