So it could have a denominator that when set = 0, gives

x=3,

So its denominator could be x-3.  So the equation could

be like this:   

That means its numerator would have to be of less degree than 
its denominator.  So if its denominator is x-3, which is of 
degree 1, then its numerator would have to be of degree 0, 
which would be a constant, say, k.  Then the equation could

be like this:   

We substitute x=4 and y=2 into









So substituting k=2, the equation could be this function:



or if we use function notation:



Edwin