Question

Question 73

In each of the following figures, write, if any (i) each pair of vertically opposite angles, and (ii) each linear pair.

Answer 1

Vertically opposite angles are the angles opposite to each other when two lines cross. A linear pair is a pair of adjacent angles whose non-common sides are opposite rays. Following are vertically opposite angles and a linear pair in the above figure.

$\begin{array}{ccc}\text{Figure}& \text{Vertically opposite angles}& \text{Linear pair}\\ \text{(a)}& \angle 1,\angle 3;\angle 2,\angle 4;\angle 5,\angle 7;\angle 6,\angle 8& \angle 1,\angle 2;\angle 1,\angle 4;\angle 4\angle 3;\angle 3,\angle 2;\angle 5,\angle 8;\\ & & \angle 8,\angle 7;\angle 7,\angle 6;\angle 6,\angle 5\\ \text{(b)}& \text{Nill}& \angle ABD,\angle DBC;\angle ABE,\angle EBC\\ \text{(c)}& \text{Nill}& \text{Nill}\\ \text{(d)}& \angle ROQ,\angle POS;\angle ROP,\angle QOS& \angle ROP,\angle POS;\angle ROT,\angle TOS;\angle QOS,\angle SOP;\\ & & \angle QOT,\angle TOP;\angle ROQ,\angle QOS;\angle ROQ,\angle ROP\end{array}$