For this all you need is to balance the equation out with the variables (a) on one side and the number on the other. Also remember that what you do to one side you do to another. So here we have 4=3a-14. You should add the 14 to both sides, on one side to cancel out the 14 and add the 14 on the other side to balance it out. Now you have 18=3a. Divide by 3 on both sides to isolate the variable a and you have your answer. A=6