How to Multiple Regression Forecast Using HP 17BII?

[AraragiMonogatari]

I was able to pick up my HP 17BII from eBay. Now I am trying to learn how to use it. I've pretty much got the hang of how to use it but now I am experimenting on how to properly do Multiple Linear Regression with 2-3 variables. I am not quite sure how the programming works on it, but I am willing to learn. The reason why I wanted the 17BII, the programming functions that comes with it and its solver function.