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Triangle Sum Theorem

Discovering Triangle Sum Theorem

Move around points A, B, and C to form at least three different types of triangles. Record the sum of the interior angles for each triangle you create.

Add the angles of the triangle you created

A + B + C = ?

Change the angles of your triangle. Add the angles of this 'different' triangle.

A + B + C = ?

Change the angles of the triangle one more time. Add the angles of this third triangle.

A + B + C = ?

What do you notice about the sum of all three interior angles for each triangle you created?