Prove that the bisectors of a pair of vertically opposite angles are in the same straight line.

Prove that the bisectors of a pair of vertically opposite angles are in the same striaght line.

Name two pairs of vertically opposite angle in the figure.

Name two pairs of vertically opposite angles in the figure.

In identity: Two pairs of vertically opposite angles.

Prove that vertically opposite angles are equal.

In the figure identify. The pairs of vertically opposite angles.

If two parallel lines are intersected by a transversal then prove that the bisectors of any pair of alternate interior angles are parallel.

Indicate which pair of angle are vertically opposite angles.

Angle between pair of straight line

A transversal intersects two parallel lines. Prove that the bisectors of any pair of corresponding angles so formed are parallel.