Answer:
D
Step-by-step explanation:
Remark
The tangent is described as the ratio of the side opposite the reference angle divided by the side adjacent to the reference angle.
In this case
The reference angle is B
The side opposite is AC and it has a value of 4
The side adjacent is BC and it has a value of 3
Hypotenuse
If you are finding either the sine or cosine of any angle, you need the hypotenuse.
AB^2 = 4^2 + 3^2 = 16 + 9
AB^2 = 16 + 9
AB^2 = 25
Take the square root of 25
AB = 5
Cos(A)
The cos(A) = adjacent / hypotenuse
Adjacent = AC = 4
Hypotenuse = AB = 5
Cos(A) = a/h
Cos(A) = 4/5 which is D
