Find the value of the trig function indicated

Answer:
A. (2√13)/13
Step-by-step explanation:
Recall, SOHCAHTOA.
Thus,
Cos θ = Adjacent/Hypotenuse
Adjacent = 16
Hypotenuse = 8√13
Therefore,
Cos θ = 16/(8√13)
Rationalize
Cos θ = (16*√13)/(8√13*√13)
Cos θ = (16√13)/(8*13) = (2√13)/13