User:Bjc
[center][b]bjc's Entry:[/b][/center] 3-4-5 triangle with circumcircle/center, incircle/center, orthocenter, centroid and 3 excircles [asy] size(12cm); dot((0,0)); dot((4,0)); dot((0,3)); dot((2,1.5)); dot((1,1)); dot((1.333,1)); dot((6,6)); dot((-2,2)); dot((3,-3)); draw((0,0)--(4,0)--(0,3)--(0,0)); draw((0,3)--(2,0)); draw((4,0)--(0,1.5)); draw(circle((2,1.5) , 2.5)); draw(circle((1,1) , 1)); draw(circle((6,6) , 6)); draw(circle((-2,2) , 2)); draw(circle((3,-3) , 3)); draw((-2,4.5)--(8,-3)); draw((0,0)--(2,1.5)); draw((0,-4.5)--(0,6.5)); draw((-2.5,0)--(6.5,0)); label( "" , (0,0), SW); label( "" , (4,0), E); label( "" , (0,3), N); label( "" , (1.33333,1) , S); label( "" , (2,1.5), NE); label( "" , (0,0)--(0,3) , W); label( "" , (0,0)--(4,0) , S); label( "" , (0,4.6)--(3.9,0)); label( "" , (1,1) , W); label( "" , (6,6) , SW); label( "" , (-2,2) , SW); label( "" , (3,-3) , S); [/asy]