In order to solve for 'x' (or any variable in this matter!), you must isolate it. In order to isolate it, you will probably have to do some of the following: 1. Addition 2. Subtraction 3. Division 4. Multiplication (Rarely used, only when there are fractions in play)
I'll give you a few examples of all of these in play.
x - 1 = 3 In this case, we must use addition to isolate x. Add 1: x - 1 + 1 = 3 + 1 x = 4
Subtraction: x + 1 = 2 In order to isolate x, we have to subtract both sides by 1: x + 1 - 1 = 2 - 1 x = 1
Division: 2x = 4 In order to isolate x, we have to divide by 2: 2x/2 = 4/2 x = 2
Multiplication: x/2 = 4 In order to isolate x, we have to multiply both sides by 2 to remove the denominator of the fraction 2*x/2 = 4 * 2 x = 8
Those are the most common ways of solving for a variable in a mathematics question. If you have a question, just ask. :) Good luck!