If you drive directly north, you are following a path that looks like a perfectly vertical line. Turning to drive directly east has you on a perfectly horizontal path. To connect where you are after that to where you started, you will construct what happens to be the hypotenuse of a right triangle. We can solve for this length (we will call it "c") by using Pythagorean's Theorem.

and

. Add to get that

and c = 74. There you go!