adding and subtracting rational expressions

[czagara]

Ok I need help doing the following problems.
I don't even know where to begin and they have to be in the simplest form.
1. 2/x +2/y


2. 6-8/x-x

 

[fasteddie65]

1. 2/x + 2/y

Adding requires a common denominator. In this problem, we can use xy as the LCD.

2y/(xy) + 2x/(xy) = (2x + 2y)/(xy)


2. 6-8/x-x

This one is unclear. Parentheses would be helpful. It looks like it could be 6 - 8/x - x. Writing it as (6 - 8)/(x - x) doesn't make any sense at all.

If it is as I have written it, then the LCD would be x.

6x/x - 8/x - x^2/x = (6x - 8 - x^2)/x

 

[czagara]

Thanks so much! Sorry, I have never done this before, this is my first time. I will remember to use parentheses. I have a question though, the first problem the answer you gave me, wouldn't you just write it as 2x+2y as the final answer or do you have to write it over the denonimator? I just have to have it in simplest terms. Thats why I ask? Its so confusing.