distance bweteen (x1,y1) and (x2,y2) is
[tex]D= \sqrt{(x2-x1)^2+(y2-y1)^2} [/tex]
so disatnce between (6,2) and (9,12) is
[tex]D= \sqrt{(9-6)^2+(12-2)^2} [/tex]
[tex]D= \sqrt{(3)^2+(10)^2} [/tex]
[tex]D= \sqrt{9+100} [/tex]
[tex]D= \sqrt{109} [/tex]
the distance is√109 units
