Question

A boat is 400 feet away from one dock and 500 feet away from the another dock. the angle between the paths is 45°. what is the approximate distance between the docks?

Answer 1

• The approximate distance between the docks is 357 feet

Explanation:

Let the distance between docks be d.

This is the opposite side to 45° angle of triangle with other sides 400 ft and 500 ft.

Use the law of cosines to find the value of d:

• 
  `d = √(400^2+500^2-2*400*500*cos45) =357` (rounded)