Answer:
Explanation:
Prove: The opposite sides of parallelogram are equal.
Proof: The given points are A(0,0) and D(c,d) are:
Using distance formula, we have

The given points are B(b,0) and C(b+c,d) are:
Using distance formula, we have

The given points are A(0,0) and B(b,0) are:
Using distance formula, we have

The given points are C(b+c,d) and D(c,d) are:
Using distance formula, we have

Hence, AD=BC and AB=CD, therefore opposite sides of parallelogram are equal.