In coordinate geometry, the distance formula is used to find the distance between two points on the coordinate plane. If you have two points and , the distance between them is given by the formula:

d = sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}

This formula is derived from the Pythagorean theorem by treating the difference in -coordinates and -coordinates as the legs of a right triangle, with the distance between the points being the hypotenuse.