Question

find the distance between a (3, -2) and b (-5, 1)

Answer 1

\[d=\sqrt{(x1-x2)^2 + (y1-y2)^2}\]

Answer 2

If you graph the points on a piece of graph paper and then drop a line from the upper point straight down to where it meets a horizontal line from the other point, you'll see that you have a right triangle, and Yahoo!'s formula is simply the Pythagorean theorem in action, the distance between the two points being the hypotenuse.