Question

Quadrilateral ABCD has vertices A(1, 0) B(5, 0) C (7, 2) D(3, 2). Use slope to prove that ABCD is a parallelogram. Show all of your work for full credit.

Answer 1

AD slope = (0 - 2)/(1-3) = 1

BC slope = (0-2)/(5-7) = 1

The line segments AD and BC have the same slope, so both line segments are parallel.

AB & CD slopes = 0 

AB & CD will be horizontal since there is no change in their Y-values thus both segments are parallel to each other

So ABCD is a parallelogram