# Alternate Interior Angles definition

## Online Tutoring Is The Easiest, Most Cost-Effective Way For Students To Get The Help They Need Whenever They Need It.

When a line is intersecting the two parallel lines then the angles which are on the opposite side of the transversal line are called alternate interior angles. The alternate interior angles are always equal. The line which intersects the other two parallel lines are called as the transversal line. When one of the alternate interior angles is given it is easy to find out the other angles also.
Following are the examples which are based on the alternate interior angles concept.

Example 1:  Two lines are cut by a transversal line and one angle is given as 110 degrees. Then find out the alternate interior angle of this angle.

Solution 1: Given that two lines are cut by a transverse line then 4 alternate interior angles are made. We know that alternate interior angles are always equal. One of the angle is given as 110 degrees then the other angle is also 110 degrees.

Example 2:  Given that two lines are intersected by a transversal line and one of the interior angles is given as 100 degrees. Then find out the other angles.

Solution 2: - Given that one of the alternate interior angles is given as 100 degrees. We know that the adjacent angles will sum up to 180 degrees so the adjacent angle would be 80 degrees. Now the required two alternate interior angles are 100 degrees and 80 degrees. So now all the interior angles are 100 degrees, 80 degrees, 100 degrees and 80 degrees.