How do i figure out input and output

Compare the subtraction problems 6/8 - 5/8 = 1/8 and 6/9 - 7/9 = 1/9 why is the answer to the first problem positive and the answer to the second problem negative

Which graph represents the solution set for the given system of inequalities? x+2y< 3 x+y> 4 3x-2y> 4

Need same math paper but the back now i hope your able to read it cleary i need with hw