Okay so this seems like a very simple problem to me but I can't figure it out so I definitely need some help. I'm not a mathematician but a programmer and in this case I need to figure out how to get the curve that passes through 3 points. I know this can be done easily with substitution but that tends to requires human logic in order to decide what equations to use in which order. I need another method. I need to be able to do this programmatically. I know when I put 3 points into the TI-83 and ask it to do a Quadratic Regression it will give me a function and plot a graph in y = ax2 + bx + c That's what I am looking for a method of solving for y = ax2 + bx + c from 3 points hopefully without substitution. I hope I am making sense. Thanks for any help.