29.6 °
Explanation
we have a right triangle( a triangle with an angle of 90°), so we can use a trigonometric function
so
Step 1
a) Let
[tex]\begin{gathered} \text{angle}=\text{ ?} \\ \text{ hypotenuse( the longest side)= 23} \\ adjacent\text{ side= }20 \end{gathered}[/tex]so, we need to use a function that relates those values, it is
[tex]\begin{gathered} \cos \emptyset=\frac{adjacen\text{t side}}{\text{hypotenuse }} \\ \text{where }\emptyset\text{ is the angle} \end{gathered}[/tex]b) replace the values in the function and solve for the angle
[tex]\begin{gathered} \cos \emptyset=\frac{adjacen\text{t side}}{\text{hypotenuse }} \\ \cos \text{ ? =}\frac{20}{23} \\ \text{ inverse cosine in both sides } \\ \cos ^{-1}(^{}\cos \text{ ?) =}\cos ^{-1}(\frac{20}{23}) \\ \text{ ? = }29.59\text{ \degree} \\ \text{rounded to 10th} \\ \text{ ? = }29.6\text{ \degree} \end{gathered}[/tex]therefore, the answer is
29.6
I hope this helps you