Proving Theorems with Coordinate Geometry Practice Test

Compute distances and show $AB=BC$ and $CD=DA$, so opposite sides are parallel.

Compute slopes and show $m_{AB}=m_{BC}$ and $m_{CD}=m_{DA}$, so adjacent sides are parallel.

Compute slopes and show $m_{AB}=m_{CD}$ and $m_{BC}=m_{DA}$, so both pairs of opposite sides are parallel.

Compute slopes and show $m_{AB}$ is the negative reciprocal of $m_{CD}$, so opposite sides are parallel.