The Solution.
The reflex angle DBC can be calculated as below:
[tex]\angle DBC=360-84=276^o\text{ ( angle at a point)}[/tex][tex]So,\text{ }\angle DBA=\angle CBA=\frac{276}{2}=138^o[/tex]
Note that: angle BDA = angle BCA = 24 degrees
Thus, considering triangle CBA (which is similar to triangle DBA), we can find angle BAC.
[tex]\angle BAC+138+24=180\text{ (sum of angles in a triangle)}[/tex][tex]\begin{gathered} \angle BAC=180-(138+24) \\ \text{ =180-162} \\ \text{ =18 }^o \end{gathered}[/tex]
Therefore, the correct answer is 18 degrees.
