7x +3y = 8
6x -3y =5
First solve for X by adding the two equations together:
13x = 13
Divide both sides by 13:
x = 13 / 13
x = 1
Replace x with 1 in the first equation:
7(1) + 3y = 8
Solve for y:
7 + 3y = 8
subtract 7 from each side:
3y = 1
Divide both sides by 3:
y = 1/3
Now solve for x-y :
1 - 1/3 = 2/3
The answer is B. 2/3
