Multiplying Fractions
In multiplying fractions, you simply multiply straight across the numerator and straight across the denominator. If you have "a" divided by "b" times "c" divided by "d," that just equals "a" times "c" divided by "b" times "d." Here's an example. The only issue with this is that you must, simply must, go ahead and simplify everything as much as possible (meaning to go ahead and factor). We notice this x squared minus 25. Let's just factor that into x + 5 times x - 5. Divided by this x squared minus 3x minus 10 can be factored into x - 5 times x plus 2. And the x plus 2 and the x do not need to be factored considering they are already prime. We simply multiply that by x plus 2 divided by x. And you’ll notice, some things in the top will actually cancel out with some things in the denominator. So, notice, these x plus 2's will cancel out, and also, the x minus 5's. So, just multiplying straight across the top, we have - the only one left, which is x plus 5, and in the denominator, just an x.