Challenge 20: Copy vs. Construct a Congruent Triangle
- Gerry Stahl
Two segments are called “congruent” if they are equal length. Two triangles are called “congruent” if all their corresponding sides are congruent. In this challenge, a triangle ABC is copied two ways: with copy-and-paste to create A1B1C1 and by copying each side length with the compass tool to construct triangle DEF. To copy and paste ABC, first select the triangle or the whole area around the triangle with the Move arrow tool and then use the Edit menu—first Copy and then Paste—and move the copy where you want it. Which triangles do you think will stay congruent with the drag test?