Solve for
x. Round to the nearest tenth of a degree, if necessary.

Answer:
[tex]\displaystyle x \approx 30.8[/tex]
Step-by-step explanation:
Note that the figure is a right triangle, and that we are given the length of the side adjacent to x and the hypotenuse of the triangle.
Therefore, we can use the cosine ratio. Recall that:
[tex]\displaystyle \cos \theta = \frac{\text{adjacent}}{\text{hypotenuse}}[/tex]
The adjacent side is 8.5 and the hypotenuse is 9.9. Therefore:
[tex]\displaystyle \cos x = \frac{8.5}{9.9}[/tex]
We can take the inverse cosine of both sides:
[tex]\displaystyle x = \cos^{-1} \frac{8.5}{9.9}[/tex]
Use a calculator. Hence:
[tex]\displaystyle x \approx 30.8[/tex]