Answer:
D. 12.3 ft
Step-by-step explanation:
This problem requires the use of trigonometric ratios. This one specifically uses the cosine ratio as it provides the hypotenuse and is asking for the side that is adjacent to the angle.
cos(40°)=a/16
cos(40°)×16=a/16×16
cos(40°)×16=a
a=12.256 ft
The length of side a is D. 12.3 ft.
