How To Calculate A Transversal’S Inner Angle?

If a transversal cuts across parallel lines, the interior angles are supplementary and add to 180°. When a transversal intersects two lines, the angles formed on the alternate side of the transversal and inside the two lines are called alternate interior angles. When the two lines cut by the transversal are parallel, then the resulting angles can be categorized into several types such as interior angles, exterior angles, pairs of corresponding angles, pairs of alternate interior angles, pairs of alternate exterior angles, and others.

Interior angles lie in the area enclosed between two parallel lines cut by a transversal. When two parallel lines are crossed by a transversal, the pair of angles formed on the inner side of the parallel lines but on the opposite sides of the transversal are called alternate interior angles. These angles are equal when they are formed by cutting two parallel lines with a transversal.

To find the sum of the interior angles of a triangle, draw a parallel line to one of the sides and notice that the other two sides are transversal. Then, use the fact that alternate angles (interior or exterior) are equal when they are formed by cutting two parallel lines with a transversal to find the consecutive interior angles.

As per the alternate interior angles theorem, when a transversal intersects two parallel lines, each pair of alternate interior angles are equal. Conversely, each pair of alternate angles around the transversal are equal to each other. The two angles can either be alternate interior angles or alternate exterior angles.