Hi,
Again, we want to work on isolating the variable a. Let's start doing this by first getting rid of the 3.
We must do the inverse of the operation, which in this case will be subtraction since the 3 is positive. Also, always remember that when we do something on one side of the equation, we must do it on the other.
4a + 3 - 3 = 11 - 3
4a = 8
Since the 4 is multiplying our variable a, this means the inverse of the operation will be division. To fully isolate a by getting rid of the 4, we will divide by 4 on both sides.
4a / 4 = 8 / 4
a = 2
Hopefully, this helps.