Name: __________________________ Date: _______________ Period: _________
PMI Proof Activity: Triangle Sum Theorem
1. Draw any type of triangle in the space below the line using a ruler and pencil (the
bigger the triangle, the better).
2. With scissors, cut out your triangle.
3. Tear off each vertex from your triangle.
4. Place them next to each other, without leaving space between the edges.
5. What do you notice about the new angle created? (Hint: What type of angle is
it?)
Geometry – Triangles
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