Please find the attached diagram for a better understanding of the solution given here.
B is the base of the Vertical Drop. Thus, AB=32 feet.
AC is the water slide and thus the length of AC is 350 feet.
We need to find the angle of depression which in this case is [tex] \angle X [/tex].
As can be seen from the diagram, [tex] \angle Y [/tex] and [tex] \angle X [/tex] are alternate interior angles where the water slide, AC, is the transversal and thus they will be equal.
therefore, [tex] \angle X = \angle Y [/tex]
Let us make use of the [tex] \Delta ABC [/tex] to find [tex] \angle Y [/tex] using the Sine trigonometric ratio.
Thus, [tex] Sin (\angle Y)=\frac{Opposite Side}{Hypotenuse} =\frac{AB}{AC} [/tex]
[tex] \therefore Sin(\angle Y)=\frac{32}{350} [/tex]
[tex] \angle Y=Sin^{-1}(\frac{32}{350})=\approx5.246^0 [/tex]
Thus Angle of Depression is [tex] 5.246^0 [/tex], which the required answer.