so thi sis really simple since you have an equal sign so
(n/3)-(5n/6)=1/3
to subtract fractions, make the bottom number the same
n/3 times 2/2=2n/6
(2n/6)-(5n/6) or (2n-5n)/6 so
-3n/6=1/3
multiply both sides by 6
-3n=6/3=2
-3n=2
divide both sides by 3
-n=2/3
mmultiply boht by -1
n=-2/3
tada
n=-2/3