You can put this solution on YOUR website! (Please put numerators and denominators in parentheses:
(5x^2-45)/(15-5x) * (2x^2-6x)/(x+3)
Without the parentheses the problem is unclear. And tutors are more likely to help when the problem is clearly stated.)
As you probably learned long ago when fractions were simpler, it is to your advantage to cancel common factors before multiplying fractions. This is not only still true, the advantage is even greater than it was before.
To cancel factors we need to know what the factors are. So we start by factoring:
Since x-3 and 3-x are negatives of each other, it will help if we factor out a -1 from one of them:
Now we can start canceling:
leaving
This is much easier to multiply than what we started with! This simplifies as follows:
P.S. I have rechecked my solution and there is indeed an error. It is correct up to:
Correctly simplifying it we get:
(