Answer: [tex]4004.76\ ft[/tex]
Step-by-step explanation:
Given
inclination is [tex]\theta=75^{\circ}[/tex]
Mountain is [tex]h=3900\ ft[/tex] high
Cable is tied [tex]x=910\ ft[/tex] from the base of the mountain
From the figure, length of the shortest path is [tex]l[/tex]
It is given by using Pythagoras theorem
[tex]\Rightarrow l^2=3900^2+910^2\\\Rightarrow l=\sqrt{(3900)^2+(910)^2}\\\Rightarrow l=4004.76\ ft[/tex]