Step-by-step explanation: To figure out where the missing point, <em>D</em>, would go, you have to figure out which side DE is congruent to and what side is missing. I saw that DE is correlates to the base of the triangle because that's the only one of that length. From there, I counted up from the center of the base, <em>DE</em>, to find a good place for the vertex, and made sure it was the same exact distance from <em>DE </em>as <em>C </em>is from the base of the first triangle.
