If we set β = f(1), then for any real number x, we have f(x) = βx and the graph of this function is the straight line in the plane passing through the origin with slope β.

Solving linear equations ... An identity is an equation which is always true, ... How to plot straight line graphs; NEW: Working out equations of a line and calculating gradient; ...

It only makes sense. I did linear regression in google docs and I did it for python. But what if you neither of those? Can you do it by hand? Why yes. Suppose I take the same data from the pylab ...