Question

$ABCD$ is a quadrilateral with $\angle A={80}^{\circ },\angle B={40}^{\circ },\angle C={140}^{\circ },\angle D={100}^{\circ }$.
(i) Is $ABCD$ is trapezium? (ii) Is $ABCD$ is parallelogram?
Justify your answer.

Answer 1

ABCD is neither a parallelogram nor a trapezium . It can be justified using basic sum property of co-interior angles to be 180 of parallel lines .