How do you?

[Zfuss12]

What do you need to prove to prove a diagram is an isosceles trapezoid if you are given 4 points...I know how to do the equations(slope, distance..etc.) I just dont know what i need to prove?

 

[pka]

The four points should create two line segments that are parallel.
And two line segments that do not intersect but have the same length.

 

[Zfuss12]

Thanks a lot I appreciate the help!