This week in PreCalc 11 we learned about adding and subtracting rational expressions with binomial and trinomial denominators. So the first step in any adding or subtracting of expressions, you need to simplify the whole equation, ex.
next with fractions, you need to find a common denominator then you can continue with the solving, ex.
Then from there you have to simplify it the most simple form.
Then for subtracting you just have to do the same but obviously subtract.