CHECK OUT SHMOOP'S FREE STUDY TOOLS:
Congruent Triangles
CHECK OUT SHMOOP'S FREE STUDY TOOLS:
Triangles on the Coordinate Plane Examples
Example 1
Why do fourlegged tables sometimes wobble, but threelegged tables never wobble? 
Example 2
Find the missing coordinates of the triangle.

Example 3
What are the lengths of each side of the triangle? Is it an equilateral, isosceles, or scalene triangle?
