On my log-log plot, the Linear curve fit does not appear as a straight line. Why?

On a log-log or semi-log plot, a Linear curve fit may not appear as a straight line. This is because the divisions along a log scale are not equally spaced. However, it is possible to get the appearance of a straight line using one of the following curve fits:
On a log-log plot (both axes are logarithmic), use a Power curve fit.

On a semi-log plot with a linear Y axis (X axis is log), use a Logarithmic curve fit.

On a semi-log plot with a linear X axis (Y axis is log), use an Exponential curve fit.