(Right angle Trigonometry) Please help me solve and explain!

Answer:
31.3
Step-by-step explanation:
Reference angle given = 56.1°
Hypotenuse = 56.1
Adjacent side = x = ?
We would apply CAH, which is:
Cos 56.1° = Adj/Hyp
Cos 56.1° = x/56.1
56.1 × Cos 56.1° = x
31.2895006 = x
x = 31.3 (approximated to the nearest tenth)