I cannot think of a better way to explain this. I hope it makes sense.
Mathematical question:
Let the origin be $O=\left[0,0\right]$.
Let the pivot point be $P=\left[P_x,P_y\right]$.
Let the scale factor be $s$, where the scale in both $x$ and $y$ are the same.
Let the translation be $T=\left[T_x,T_y\right]$.
How does one calculate $T$ in order to simulate zooming in to or away from the pivot point?
Graphical example:
Zooming in on the top-left white square.
Before zoom:
After zoom:


I was completely overthinking this.
$T=\left[P_x\times\Delta{s},P_y\times\Delta{s}\right]$