hi im new here and i hope you can help me.. i need help with 3 parts to a math question that i have been struggling with all day.

a. x+2/3 - x + 5/2x

b. x+3/x-4 + 3x-1/5x-20

c. 3/x2 +7x +12 + 2/x2 - 2x - 15

and help would be greatly appreciated..