Given:
BD is parallel to XY.
One of the angle is 85°
To find:
The value of y.
Solution:
Parallel lines BD and XY cut by a transversal line.
Angle y and 85° are alternate interior angles.
Alternate interior angle theorem:
If two parallel lines are cut by a transversal line, then the pairs of alternate interior angles are congruent.
⇒ y = 85°
The value of y is 85.
