Question:
In the adjoining figure, AOB is a straight line. Find the value of x.
Solution:
We know that the sum of angles in a linear pair is $180^{\circ}$.
Therefore,
$\angle A O C+\angle B O C=180^{\circ}$
$\Rightarrow 62^{\circ}+x^{\circ}=180^{\circ}$
$\Rightarrow x^{\circ}=\left(180^{\circ}-62^{\circ}\right)$
$\Rightarrow x=118^{\circ}$
Hence, the value of $x$ is $118^{\circ}$.