Answer:
The answer to your question is x = 66.42° and x = 293.6°
Explanation:
Data
cos x = 2/5
x = ?
Process
1.- Look at the sign of 2/5.
2/5 is positive so the angle we are looking for is in the first or the fourth quadrant.
2.- Remember the side that the trigonometric function relates
cos x = Adjacent side / hypotenuse
then, adjacent side = 2
hypotenuse = 5
3.- Get cos⁻¹ x
cos⁻¹x = x = 66.42°
4.- If the angle is in the first quadrant x = 66.42°
5.- If the angle is in the fourth quadrant x = 293.6°