__Definition of Distance Formula__

The distance formula can be obtained by creating a triangle and using the Pythagorean Theorem to find the length of the hypotenuse. The hypotenuse of the triangle will be the distance between the two points.The subscripts refer to the first and second points; it doesn't matter which points you call first or second.

x2 and y2 are the x,y coordinates for one point

x1and y1 are the x,y coordinates for the second point

d is the distance between the two points

x2 and y2 are the x,y coordinates for one point

x1and y1 are the x,y coordinates for the second point

d is the distance between the two points