Answer:
43.76 degrees.
Explanation:
The trigonometric function cosine relates the adjacent side with the hypotenuse. Therefore, we can find the missing angle using the following equation:
[tex]\text{cos}\theta=\frac{Adjacent}{Hypotenuse}[/tex]So, replacing the values, we get:
[tex]\cos \theta=\frac{13}{18}=0.7222[/tex]Therefore, the missing angle is:
[tex]\begin{gathered} \theta=\cos ^{-1}(\frac{13}{18}) \\ \theta=43.76 \end{gathered}[/tex]Then, the missing angle has a measure of 43.76 degrees.