Where is the problem at? give me the url
This really depends on the fraction; if there are variables in the equation, if they are full numbers,etc. I'd really recommend looking up khan academy on YouTube and that will really help you out!
Answer:
<h2><em><u>2a</u></em></h2>
Step-by-step explanation:
(a+b-c)-(b-a-c)
= a + b - c - b + a + c
= a + a + b - b - c + c
= <em><u>2a (Ans)</u></em>