Question

Observe the figure and find the value of $x$.

Answer 1

We know that, if two angles are complementary, then their sum is ${90}^o$.

Then, $\angle COB+\angle COA={90}^{\circ }$

$\Rightarrow 3x+2x={90}^{\circ }$

$\Rightarrow 5x={90}^{\circ }$

$\Rightarrow x={18}^{\circ }$.