Angles that are equal and opposite from each formed by the intersection of two lines. In the image to the right, angles ABC and DBE (highlighted in blue) comprise a pair of vertical angles; ABD and CBE (highlighted in purple) comprise a second pair. Check out this link to MathLeague for more information on vertical angles.

A pair of non-adjacent angles formed by intersecting lines; also called vertically opposite angles

A pair of opposite angles that is formed by intersecting lines.

The pair of angles that are directly across from each other when two straight lines intersect. Angles a and b at the right are an example of vertical angles.

the opposite angles formed by the intersection of two lines. Vertical angles are equal in measure.

pairs of angles formed from two intersecting lines; in the adjacent figure, angles 1 and 2 are vertical angles.

the opposite angles formed when two lines intersect.

The two nonadjacent angles formed when two straight lines intersect

If and intersect at point so that point is between points and and also between points and , then APC and BPD are a pair of vertical angles. Angles APD and BPC are also a pair of vertical angles (Lesson 2.4).

The pair of angles that are directly across from each other when two straight lines intersect. They are always non-adjacent angles.