Distance between the rocks = 81.36 feet
In the question,
Height of the person standing on the sand pile from the ground = 15 foot
Angle of depression of a rock on one side = 17°
Angle of depression of other rock on another side = 25°
So,
In the triangles formed, we get,
[tex]tan(25)=\frac{15}{x}\\x=\frac{15}{tan(25)}\\x=32.18\,foot[/tex]
Also,
On the other side of the pile,
[tex]tan(17)=\frac{15}{y}\\y=\frac{15}{tan(17)}\\y=49.18\,foot[/tex]
So,
The distance between the rocks is given by = x + y = 32.18 + 49.18
Distance = 81.360 foot