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How to Solve for X

Algebra can be scary at first. Suddenly instead of just numbers, you are dealing with letters in math class! One of the first things you'll need to do in algebra is learn to solve for x.

Things You'll Need

  • Paper
  • Pencil
  • Math Problems that need solving!
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Instructions

    • 1

      Solving for x can sound scary but it's not! When you see x in an equation, it's simply there representing an unknown number. Our goal is going to be discovering what that unknown number is!

    • 2

      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!

    • 3

      Let's look at a simple equation first. 2 + x = 7. How do we get x by itself? We need to subtract 2 from both sides: 2 - 2 + x = 7 - 2. Now we simplify the equation by doing the simple math: x = 5. See that? We already found the answer! This isn't so scary now, is it?

    • 4

      Not every equation is going to be quite that simple. Many will have more steps than the first example. Let's try another one. 5x - 10 = 5. First, add ten to both sides: 5x - 10 + 10 = 5 + 10. That simplifies to 5x = 15. Now that we got ride of the 10, we need to get the 5 away from the x. We do this by dividing both sides by 5" 5x/5 = 15/5. Simplified, that is x = 3. We solved for x again!

    • 5

      As we continue through the algebra book, you might find some equations that have more than one letter! Is it really possible to solve equations with two or more letters and numbers in it! Yes! The next thing we need to learn is that it's OK to have letters in your answer.

    • 6

      Let's try one last equation together. 5x + 3 = 10y + 18. We want to solve for x, just like before. So let's 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!

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