Windows XP Pro SP3
Excel 2007

I wrote a pretty simple interface to help my daughter with graphing
algebra functions. The form allows her to specify the number of data
points, a range of X values and coefficient values for polynomials,
and then I simply write the coordinates to a sheet and the pre-made
chart automatically graphs the function. What I can't figure out is
how to force the X and Y axes to be the same scale. I'd also like to
be able make both axes intersect at other's zeros like in a Cartesian
System. I can determine if the origin should be "visible" based on
the range of values specified in the form, but I can't seem to make
the Y axis be anywhere but the sides of the graph.

Oh, in case I wasn't clear enough, I'm looking to do this in VBA. Any
and all help appreciated, thanks!!