Review of the Pythagorean Theorem: Introduction

Map showing Gulf of Finland, with Estonia to the south and Finland to the north

In the map above, you see the Gulf of Finland with Tallinn, Estonia to the South and Helsinki, Finland to the North.  If we wanted to know how far apart these two cities are, we could use their latitude and longitude and the Pythagorean Theorem to calculate the distance.  In this section, we will review the Pythagorean Theorem and how this sort of calculation would be done.