\input pstricks
\input fp
\FPmessagesfalse
\input vec2d

Bissectrices met ingeschreven cirkel in $\Delta PQR$ met $PQ = 6$, $\angle P =
78^\circ$ en $\angle Q = 48^\circ$.

\VDDstart
  \VDDtriangletwoangles R:P(0,0)Q(6;-8):78,48
  \VDDdcanvas1:1
    \VDDdlpolygon PQR
    \VDDcdldeellijnpart T:QRP
    \VDDcdldeellijnpart U:PQR
    \VDDcdldeellijnpart V:RPQ 
    \VDDcppintersect M:TR:UQ
    \VDDdeflinepoint l:PQ
    \VDDcleadline m:l:M
    \VDDcintersect S:lm
    \VDDcplength\length:MS
    \VDDdcircle M:\length
  \VDDdcanvasend
\VDDend

Middelloodlijnen met omgeschreven cirkel in $\Delta ABC$ met $AB = 7$, $BC = 6$
en $AC = 5$.

\VDDstart
  \VDDtriangletwolengths C:A(0,0)B(7;-10):5,6
  \VDDdcanvas1:1
    \VDDdlpolygon ABC
    \VDDcavg D:AB
    \VDDdeflinepoint l:AB
    \VDDcleadline m:l:D
    \VDDdwholeline m
    \VDDcavg E:BC
    \VDDdeflinepoint l:BC
    \VDDcleadline m:l:E
    \VDDdwholeline m
    \VDDcavg F:AC
    \VDDdeflinepoint l:AC
    \VDDcleadline k:l:F
    \VDDdwholeline k
    \VDDcintersect M:mk
    \VDDcplength\length:MA
    \VDDdcircle M:\length{}
    \VDDlpointletter ADM
    \VDDdperp MDA
    \VDDlpointletter BEM
    \VDDdperp MEB
    \VDDlpointletter CFM
    \VDDdperp MFC
    \VDDdlinepartequal ADDB
    \VDDdlinepartequal BEEC
    \VDDdlinepartequal AFFC
    \VDDdeflinepoint l:AB
    \VDDcintersect S:lk
    \VDDlpointletter SME
  \VDDdcanvasend
\VDDend

\break

Zwaartelijnen in $\Delta ABC$ met $A(0,0)$, $B(6,1)$, $C(2,4)$.

\VDDstart
  \VDDdef A(0,0)B(6,1)C(2,4)
  \VDDdcanvas1:1
    \VDDdruitjes
    \VDDdlpolygon ABC
    \VDDcavg D:AB
    \VDDcavg E:BC
    \VDDcavg F:AC
    \VDDdline CD
    \VDDdline AE
    \VDDdline BF
    \VDDlpointletter ADB
    \VDDlpointletter BEC 
    \VDDlpointletter CFA
    \VDDdlinepartequal ADDB
    \VDDdlinepartequal BEEC
    \VDDdlinepartequal AFFC
    \VDDcppintersect S:CD:AE
    \VDDlpointletter ESC
  \VDDdcanvasend
\VDDend

    %\VDDcdldeellijnpart T:QRP
    %\VDDcdldeellijnpart U:PQR
    %\VDDcdldeellijnpart V:RPQ 
    %\VDDcppintersect M:TR:UQ

    %\VDDdlpolygon PQR

    %\VDDcleadline l:m:M 

    %\VDDcppintersect S:RT:PU
    %\VDDlpointletter RSP
    %\VDDlpointautoangle UPR
    %\VDDlpointautoangle RQP
    %\VDDlnumberangles RPTUR:S
    %\VDDlnumberangles TSR:P
    %\VDDlnumberangles QRP:T
    %\VDDlnumberangles PTQ:R

\bye
