Question

The measure of $\angle x$ in degrees is

Answer 1

In $△ACD$,
$AC=AD$
$\angle ACD=\angle ADC=42$ ...(Isosceles triangle property)
In $△ABC$,
$CA=CB$
Hence, $\angle CAB=\angle CBA=y$ ...(Isosceles triangle property)
$\angle CAB+\angle CBA=\angle ACD$ ...(Exterior angle property)
$y+y=42$
$y=21$
Now, In $△$ ABD,
$x=\angle ABD+\angle ADB$
$x=21+42$
$x={63}^{\circ }$