To find the missing angle we can use the inentity for cos tha is:
[tex]\cos (\theta)=\frac{adyacent}{hypotenuse}[/tex]and in our triangle will be:
[tex]\cos (\theta)=\frac{24}{30}[/tex]and we cn solve for theta:
[tex]\begin{gathered} \theta=\cos ^{-1}(0.8) \\ \theta=36.9º \end{gathered}[/tex]