Greenestamps didn't think of the sneaky trick of eliminating an x-intercept by
putting an extra factor in the numerator and denominator to create a hole in the
curve instead of having an x-intercept. I'll use that trick.
To have those vertical asymptotes, the denominator, when set = 0, must have
roots 3 and -3, so the denominator must contain (x-3)(x+3), which has degree 2
and leading coefficient 1. That might be enough for the denominator. If so,
the numerator must also be of degree 2 and have leading coefficient 1 in order
to have horizontal asymptote y = 1. So let's try this version:
To have x-intercept 5, it must go through (5,0). So we substitute
Multiply through by 16
To have y-intercept -5/9, it must go through (0,-5/9). So we substitute
Multiply both sides by -9
Substituting in
So let's substitute those values for A and B in
Let's graph it and see what we have:
Oh darn! That has an extra x-intercept at (1,0). Aha, but I can play the trick!
I'll put a hole in the curve at (1,0) by putting in a factor of (x-1) in
the numerator and the denominator:
Then the graph has a hole at (1,0) instead of an x-intercept there.
The un-factored form of the rational function is:
Edwin