Ok. If I make my triangle bigger because I occasionally get my seams a little off and cut it down how do know how far down to cut. It would seem like I'd just get a bigger triangle? I just want to understand what should be happening mathematically because I know my sewing is imperfect and I will likely need to adjust if I'm ever going to get them "right" but I need to know how I should be adjusting, if that makes sense.