Algebra: It's a word that has struck fear into the heart of many a student, and with good reason. Algebra can be hard. You're dealing with unknown amounts, and math suddenly become less concrete. But, as with all math skills, you have to start out with the basic foundation and then build on it. In algebra, the basic foundation involves practicing equations in which you solve for x -- which simply means you have to figure out what the unknown amount is.
Learn the golden rule. The first step to solving for x is going to be getting x alone on one side of the equation and everything else on the other side. Remember the rule: What you do to one side of the equation, you must do to the other side. That's how the equation stays equal!
Start with a simple equation. The most basic algebra equation involves simple addition or subtraction with one unknown quantity, such as 2 + x = 7. How do you get x by itself? Subtract 2 from both sides: 2 - 2 + x = 7 - 2. Now simplify the equation by doing the math: x = 5.
Increase your level of difficulty. Not every equation is going be simple and may require more steps. A more difficult equation might be 5x - 10 = 5. First, add 10 to both sides: 5x - 10 + 10 = 5 + 10. That simplifies the equation to 5x = 15. Now that you've gotten rid of the 10, you need to get the 5 away from the x. Divide both sides by 5: 5x/5 = 15/5. Simplified, that is x = 3.
Continue learning more about algebra. In algebra, you might find some equations that have more than one letter. The equations may work out to where the answer for x may actually contain another letter itself. An example of this would be 5x + 3 = 10y + 18. You want to solve for x, just like before, so get x by itself on one side of the equation. Subtract 3 from both sides: 5x + 3 -3 = 10 y + 18 - 3. Simplify: 5x = 10y + 15. Now divide both sides by 5: 5x/5 = (10y + 15)/5. Simplify: x = 2y + 3. And there's your answer!
TL;DR (Too Long; Didn't Read)
The best way to get more comfortable doing algebra problems and solving for x is to practice, practice, practice.