The equation for a circle is:

Where (a,b) is the circle's center and r is the circle's radius.
First, we can find the center point of the circle. Because the two points from the problem are the endpoints of a diameter, the midpoint of the line segment is the center point of the circle.
The formula to find the mid-point of a line segment giving the two endpoints is:
M =
,

Where M is the midpoint and the given points are:
and

Substituting the values from the two points in the problem gives:
,

,


