Question

In the figure, AD =BC and AD parallel to BC. prove that AB = DC

Answer 1

this is a parallelogram and in parellogran opposites sides are parallel and equal to each other. hope this will help you. I m not sure about this

Answer 2

So since in the figure one pair of sides are equal and parallel the following fig. Is a parallelogram. And the diagnol of a parallelogram divides it into two congruent triangles that is triangle ADC and ABC. therefore by cpct (corresponding parts of congruent triangles) AB=DC.