Hello

I recently bought a Casio FX-991EX. I am in high school and orientate myself in physics. The statistics has a formula y=a+bx. I, for example, have an experiment where i get bunch of **m** (x) and **l** (y), i put those points in a graph and draw a line that suites all the points (linear regression) and calculate **k **from that line using **kl=mg**. I see that i could enter those values in the calculator and get b (**y=a+bx** where **y **is *l*, **a **is 0, **x **is *m *and **b **= *g/k*), but how can let the calculator know that a = 0 (or generally in every statistics formula that **b **or **a **is a number that i know) or something like that?