Asailboat drifts 600 meters west, makes a turn and sails 800 meters south. how far is the sailboat from its original position? explain how you got the answer if you can. i'd like to understand this question more.

The Pythagorean theorem is what is most useful here, and a calculator; for the following...
Imagine forming a triangle by creating that last leg between the starting position and the ending position; the length of that side will be our missing variable "y".

600² + 800²= y²

The sum of the two (600² & 800²) must then be square rooted to find the length

y² = 1,000,000 and the square root of y²= 1,000 (YOUR ANSWER) "y"