% Right triangle and circumscribed circle
% Classic Euclidean geometry construction in Eukleides

A = point(0, 0)
B = point(4, 0)
C = point(0, 3)

O = circumcenter(A, B, C)
r = dist(O, A)
c = circle(O, r)

draw(triangle(A, B, C))
draw(c)
label(A, "A", south west)
label(B, "B", south east)
label(C, "C", north west)