math
posted by lee .
a rope is 120 ft long and the water is 20 ft deep. how far is the anchor from a point directly below the boat?

Use Pythagoras theorem,
L = √(H²+D²)
or
L² = H²+D²
L=Length of the rope = 120'
D=Depth = 20'
H=Horizontal distance of the anchor from the boat
From
L² = H²+D²
we get
H² = L²  D²
= 120²20²
=14400  400
= 14000
Horizontal distance
= √H
= 118.3'