Lines and Angles

If two lines intersect, the vertically opposite angles are:

The sum of the angles on a straight line is:

If two parallel lines are cut by a transversal, the alternate interior angles are:

In triangle ABC, if angle A = 50° and angle B = 60°, then angle C is:

Two lines are perpendicular if the angle between them is:

If a transversal intersects two parallel lines, then the sum of the interior angles on the same side of the transversal is:

In the figure, two lines AB and CD intersect at O. If ∠AOC = 70°, find ∠BOD.

If the sum of two adjacent angles is 180°, then the two angles are called:

In a triangle, one angle is twice the smallest angle and the third angle is 20° more than the smallest angle. Find the smallest angle.

Two parallel lines are cut by a transversal. If one of the interior angles is 110°, find the measure of the corresponding exterior angle on the same side of the transversal.