Pythagorean Theorem Without Words
Based on a problem in Exeter Math 2 A 5 x 5 square and a 3 × 3 square can be cut into pieces that will ﬁt together to form a third square. How does this prove the Pythagorean Theorem.
Sum of the Angles in a Triangle
Triangle Angle Theorems
Polygons: Exterior Angles
Law of Cosines Investigation
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Difference and Slope