I got a program that I found very useful. It's a distance program that does problems like ( -4,c) (-7,7) 5 units apart. It is 392 bytes long. Here it is: Prgm Distance ClrHome Disp "(1,2)(3,4)" Disp "which is x?" Input V If V=1 goto 1 goto 2 lbl 1 Disp "Coordinants?" Input A Input B Input C Input D Disp "Units apart?" Input Q D->A goto 3 lbl 2 If V=2 goto 4 goto 5 lbl 4 Disp "Coordinants?" Input A Input B Input C Input D Disp "Unists apart?" Input Q A->B D->A C->D goto 3 lbl 5 if V=3 goto 8 Disp "Coordinants?" Input A Input B Input C Input D Disp "Units apart?" Input Q B->L A->B L->A C->D goto 3 lbl 8 Disp "Coordinants?" Input A Input B Input C Input D Disp "Units apart?" Input Q lbl 3 -A+-A->E A^2->F (D-B)^2->G F+G->G Q^2->Q G-Q->G Squareroot(E^2-4G)->H (-E+H)/2->M (-E-H)/2->N Disp M Disp N End For the X variable, just type 0. Josh