Answer = 76.23 degrees
For this question you would use trigonometry, specifically the cosine equation, which is given as:
cos(theta) = adjacent / hypotenuse
You use the cosine equation because the angle x lies between the hypotenuse and the adjacent side.
The side with the 5 would be the adjacent, as this side is where the two angles lie on.
The side with the 21 would be the hypotenuse, as this is the longest side of the triangle that is opposite the right angle.
Substituting the values into the cosine equation:
Hypotenuse: 21
Adjacent: 5
cos(theta) = 5/21
cos(theta) = 0.238...
Using arcosine (inverse function of cosine) to find the angle:
cos^-1(0.238...) = 76.23 (rounded to the nearest hundredth)
