1 Answer | Add Yours
The figure shows a quadrilateral with equal opposite sides and the interior angle made by the two with a third side are 120 degrees and 60 degrees.
As 120 + 60 = 180, the two lines are parallel to each other. This follows from the fact that in the case of two parallel lines intersected by a transversal, the sum of the consecutive interior angles is equal to 180 degrees.
As the opposite sides are parallel as well as equal in length the quadrilateral is a parallelogram.
We’ve answered 395,760 questions. We can answer yours, too.Ask a question