Question

In adjacent figure AB||CD and PQ||RS fond the value of x

Answer 1

Let the point intersecting AB and QP be 'K'
and the point intersecting AB and SR be 'L'

angle QKB = 100° [Alt. interior angles because AB is parallel to CD and PQ is the transversal]

angle BLR = 100° [Alt. interior angles because PQ and SR are parallel and AB is a transversal]

Answer 2

Vertically opposite angles are equal and also Straight angle = 180° .....

180-100= 80.So X=80°