Answer:
x ≈ 36.9°
Step-by-step explanation:
Using the cosine ratio in the right triangle
cos x = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{AB}{BC}[/tex] = [tex]\frac{12}{15}[/tex] , then
x = [tex]cos^{-1}[/tex] ( [tex]\frac{12}{15}[/tex] ) ≈ 36.9° ( to the nearest tenth )