I am learning how to graph equations. I think $y=x$ is a line and $y=x^2$ is a parabola. I have a wiggly graph. The question is to find an equation for the graph. It then asks given any graph can you find an equation for it?
I don't think it is the case.
If you have graf composed using the inaccurate values use approximation: Least squares method. If you have exact values in graf You can use interpolation method using polynome - for n point use polynome order n.