Draw lines PQ and RS intersecting at point O. Measure a pair of vertically opposite angles. Bisect them. Are the bisecting rays forming a straight line ?

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

Fill in the blanks: (i) If two angles are complementary, then the sum of their measures is _______. (ii) If two angles are supplementary, then the sum of their measures is ______. (iii) Two angles forming a linear pair are _______________. (iv) If two adjacent angles are supplementary, they form a ___________. (v) If two lines intersect at a point, then the vertically opposite angles are always _____________. (vi) If two lines intersect at a point, and if one pair of vertically opposite angles are acute angles, then the other pair of vertically opposite angles are __________.

Lines PQ and RS intersect each other at point O. If /_POR:/_ROQ=5:7, find all the angles.

If two lines intersect each other, then the vertically opposite angles are equal.

Prove that if two lines intersect each other, then the vertically opposite angles are equal.

If two lines intersect; then the vertically opposite angles are equal.

If two lines intersect prove that the vertically opposite angles are equal

Draw a line segment of 7.2 cm and bisect it. Also measure each part.

Lines And Angles|Linear Pair Axioms|Theorem (Vertically Opposite Angles)

What is Point of intersection of pair of straight line?