I failed Math every year in school, so I don't know what any of this means. I'm reading the explanations here in my math book, and I still don't understand. And I don't have these buttons on my calculator so I'm lost.

Here is an example...

**Simplify complex fractions **

7/12 + 5/16 = 43/48 Those are fractions, not division. The examples in the book are nothing like the problems I have to do. Another one is -5/9 - 14/15 = -67/45, I don't understand any of this. I know it has something to do with cross multiplying...I don't know what any of that is either.

If somebody could help me understand this, I would be forever indebted to you.

You have to find a common denominator for the fractions in order to add them.

First look for common a multiple ot 12 and 16 that is also a multiple of 48. In this case it's easy because 12x4 and 16x3 are both equal to 48x1, they are all 48. When you multiply the denominator you multiply the numberator by the same value, so

7/12 becomes 7x4/12x4 + 5x3/16x3 after you multiply this becomes 28/48+ 15/48 add the numerators and keep the denominators (do not add the 48s) you get 28+15/48 which simplifies to 43/48

The subtraction is the same. The common denominator is 45 (9x5 and 15x3) -5x5/9x5 - 14x3/15x3 becomes -25/45 - 42/45 . Next, combine the numerators keeping the denominators -25 - 42 /45 = -67/45

Teaching math over the internet isn't easy; it's too bad we can't have just a few minutes with some scratch paper. Check and see if your local community college offers math tutors, they are often free if you go to the school.

Good luck with math, if you have any more questions feel free to PM.