@options;
  repereortho(310,270,30,1,1){ 0 , moyen , noir , num1 ,i};

@figure;
  O = point( -1 , -3 );
  cerayA4 = cerclerayon( O , 4 );
  M = point( 6.13 , 1 )  { noir , rond2 };
  B = point( -5.4 , 1 );
  dMB = droite( M , B )  { noir , 7 , sansnom };
  T2 = intersection( dMB , cerayA4 , 1 )  { (-0.97,-0.7) };
  T1 = intersection( dMB , cerayA4 , 2 )  { (-0.6,-0.93) };
  sT2A = segment( T2 , O )  { violetfonce };
  sAT1 = segment( O , T1 )  { violetfonce };
  H = milieu( T2 , T1 )  { rouge , // , rond2 };
  sAH = segment( O , H )  { rouge };