I have an expression which is $\displaystyle\frac x{x+40}$.
I'm trying to find a point indicated in the graph. As you can see I drew 2 lines, one tangent to the region which it saturates, the other were it has max growth. where they intersect, I drew a line at which it has equal angle to the first two line I drew and cuts into the curve. The intersection between the 3rd line and the curve is what I wish to find. Is there anyway to mathematically determine it?

region which it saturates? – Cesareo Mar 09 '21 at 08:49