I need help you ASAP I need the answer

Answer:
[tex]\huge\boxed{<BCA = 48\°}[/tex]
Step-by-step explanation:
The measure of exterior angle is equal to the sum of the non-adjacent interior angles.
So,
∠NAB = ∠ABC + ∠BCA
105° = 57° + ∠BCA
Subtracting 57 to both sides
∠BCA = 105°-57°
Hope this helped!