You can put this solution on YOUR website! let's get rid of those horrible fractions!
Multiply each term through out the equation by 3.
Giving
this cancels out the 3's in the denominators
giving
2(a-3)=-1
multiplying out the bracket gives
2a-6=-1
adding 6 to both sides we get
2a-6+6=-1+6
simplifying gives
2a=5
dividing by 2 gives
a=2.5