The distance formula is derived from the Pythagorean theorem. To find the distance between two points (x1,y1) and (x2,y2), all that you need to do is use the coordinates of these ordered pairs and apply the formula pictured below.
Below is a diagram of the distance formula applied to a picture of a line segment
Video Tutorial on the Distance Formula
is just the Pythagorean Theorem in Disguise
Now, let's find the distance. We're basically just using the Pythagorean theorem.