Question

Question 1
In the given figure, find the values of x and y and then show that AB || CD.

Answer 1

It can be observed that,
${50}^{\circ }+x={180}^{\circ }$ (Linear pair)
$x=180-50$
$x={130}^{\circ }$

Also, $y={130}^{\circ }$ (Vertically opposite angles)
x and y are alternate interior angles for lines AB and CD and also measures of these angles are equal to each other.
$\therefore$ AB || CD.