Question 1202298
<pre>
{{{drawing(400,400,-5,11,-5,11, locate(4,1,O), locate(5,6.6,A), locate(9.1,2.4,B), locate(7.1,4.5,C),
locate(3,10,"C=(7,4)"),locate(3,9,"O=(4,1)"),locate(3,8,matrix(1,3,AB=4sqrt(2),so,AC=2sqrt(2))),
locate(4.2,4,r),
graph(400,400,-5,11,-5,11),circle(4,1,sqrt(26)),
line(5,6,9,2),line(4,1,5,6),line(4,1,9,2), line(4,1,7,4))}}}{{{

matrix(14,3,"","","",
CO,""="",sqrt((7-4)^2+(4-1)^2),
CO,""="",sqrt(3^2+3^2),
CO,""="",sqrt(9+9),
CO,""="",sqrt(18),
CO^2,""="",18,
"","","",
AO^2,""="",AC^2+CO^2,
r^2,""="",(2sqrt(2))^2+18,
r^2,""="",4*2+18,
r^2,""="",8+18,
r^2,""="",26,
r,""="",sqrt(26),"","","" )}}}

Edwin</pre>