podobni(X1, Y1, X2, Y2, X3, Y3, X4, Y4, X5, Y5, X6, Y6, TRUE) :- rasstoyanie(X1, Y1, X2, Y2, R1), rasstoyanie(X2, Y2, X3, Y3, R2), rasstoyanie(X3, Y3, X1, Y1, R3), rasstoyanie(X4, Y4, X5, Y5, R4), rasstoyanie(X5, Y5, X6, Y6, R5), rasstoyanie(X6, Y6, X4, Y4, R6), TRUE = (R1*R5 == R2*R4), (R1*R6 == R4*R3). rasstoyanie(X1, Y1, X2, Y2, R) :- R is ((X2-X1)*(X2-X1) + (Y2-Y1)*(Y2-Y1)).