I have recently had some of my first lessons in calculus. We've learned to use the well-known formula for the slope of a tangent:
When working with this formula, I was told that the equation on the left-side should be simplified such that when $h=0$, there would be no division by $0$.
Obviously, I'm extremely new to these calculus concepts.
I want to know what happens when the equation cannot be simplified and there is a division by $0$. That is, there is no solution. What does a situation like this represent? What would it look like graphically?