A. x = 2544 divided by 25
x= 101.76
B. x = 2150 divided by 20
x = 107.5
I hope this helps let me know if you need more.
The horizontal line is refered to as a fraction bar or a vinculum. There are also other names, but these two are the ones I know the best.
Your final answer for this question is -3(y-2)/2. Hope this helps.