When we solve algebraic equations, our aim is to end up with one letter on one side of the equals sign and one number on the other. This is the solution.
It doesn't matter if you end up with the letter on the left or the right, it means the same thing. (a = 6 is exactly the same as 6 = a)
We do this by using inverse operations to undo things that get in the way, but remember that we must do the same thing to both sides.
Example
Solve for a
5 - a = 10
Answer
Add a to both sides.
5 - a + a = 10 + a
Simplify
5 = 10 + a
Subtract 10 from both sides.
5 -10 = 10 - 10 + a
Simplify
-5 = a
a = -5