PLANE(0,10,0,10)
A1=5;A2=6; Gonio(A1,A2,5)
B1=2;B2=1; C1=8;C2=4
halfline(A1,A2,B1,B2,"red"); halfline(A1,A2,C1,C2,"red")
POINT(c(A1,B1,C1),c(A2,B2,C2), 1)
type(A1-0.5,A2+0.5,"A")
type(B1-0.5,B2+0.5,"B")
type(C1+0.5,C2+0.5,"C")
type(5.2,5,"87")