00:01
All right, so we are looking for a number k, such that the ordered pair k -comma -k is the same distance from negative 1 -0 as it is to 0 -2.
00:14
So what we'll do is find the distance between k -coma -k and each of these pairs.
00:20
So we'll start with negative 1 -0.
00:22
So up on the right, we have the distance between two points.
00:25
It's given by this formula.
00:26
So we're going to subtract the x coordinates and we'll subtract the y coordinates.
00:33
So we have k minus negative 1, and that's quantity squared plus k minus 0 squared.
00:41
You probably remember that's derivation is from the pythagorean theorem, sides of the right triangle.
00:49
So i have k plus 1 squared plus k squared, and then when we multiply out k plus 1 times k plus 1, you get k squared plus 2k plus 1 plus k squared...