find the distance between those points
diameter/2=radius
distance betwen (x1,y1) and (x2,y2) is
[tex]D= \sqrt{(x2-x1)^2+(y2-y1)^2} [/tex]
given
(3,7) and (7,3)
[tex]D= \sqrt{(7-3)^2+(3-7)^2} [/tex]
[tex]D= \sqrt{(4)^2+(-4)^2} [/tex]
[tex]D= \sqrt{16+16} [/tex]
[tex]D= \sqrt{32} [/tex]
D=4√2
diameter/2=(4√2)/2=2√2
radius is 2√2
