Hello I'm trying to plot log as part of an equation in mathematica and it does not seem to be working for me.

for example I'm using Plot y = 25x / log10 (x) - 50x

I'm just experimenting with different numbers and formulas to see what happens to the log curve.

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What I'm doing in more detail, is that I wanna be able to change variables so that the curve can become steeper or shallower. I wanna introduce about 4 or 5 different variables to control it.

I wanna try and mimic and simplify this formula to produce the graph above. Where the water table level is controlled by the porosity of the rock and the flow of the well. Low porosity and low discharge from the well result in a steep curve and vise versa.