# How do you combine #4/(x^2+4x-5) - 3/(x^2-1)#?

##### 2 Answers

We can factor both denominators in order to find the lowest common denominator among them.

Using Bhaskara for the first equation

For the second equation, we can find the roots simply by equaling it to zero.

Now, we can rewrite your subtraction as:

The lowest common denominator must comprise all terms in the denominators, which lead us to

Now we know our denominator is

If you want to redistribute, it'll end up like this:

Factor

Numerator: 4x + 4 - 3x - 15 = x - 11