I'm assuming all of (x^2+9) is in the denominator. If that assumption is correct, then,
One possible answer is 
Another possible answer is 
There are many ways to do this. The idea is that when we have f( g(x) ), we basically replace every x in f(x) with g(x)
So in the first example above, we would have

In that third step, g(x) was replaced with x^2+9 since g(x) = x^2+9.
Similar steps will happen with the second example as well (when g(x) = x^2)
Answer:
he made the mistake on step one, he didn't distribute correctly
Step-by-step explanation:
-5(x-1) = -5x +5
not -5x - 1
Answer:
Okay, there are many ways to find if a triangle is congruent.
Let's start with some different terminology.
For the sake of simplicity let us say that S stands for when a side is congruent for both triangles and A stands for when an angle (<) is congruent between both the triangles as well.
So, you need to memorize some rules. If you find that 2 triangles are congruent in the sense of; SSS, SAS, AAS, SAA, and ASA. One thing to remember is that Angle Side Side isn't congruent and is called <em>Donkey Theorem</em>. This theorem only works for right triangles.
One way to know if your triangle isn't congruent is if you can find a part of the triangle that is different.
I know that wasn't the best explanation but I hope it helped anyhow. :)
The answer is a I'm pretty sure