ANSWER
m∠D = 50º
EXPLANATION
Triangle DEF is:
We want to know the measure of angle D, knowing the side lengths DE (the hypotenuse of the triangle) and FD (the adjacent side to angle D). We can use the cosine of D:
[tex]\begin{gathered} \cos \angle D=\frac{59}{91} \\ \angle D=\cos ^{-1}\frac{59}{91} \\ \angle D=49.58º\approx50º \end{gathered}[/tex]
