Algebra’s like a puzzle. Know those puzzles where you gotta move the pieces around to make a picture? It’s like that. To find what number “x” is, you gotta move the numbers around, so that “x” is by itself on one side. And there’s rules. Here’s the key: you have to do the same thing to both sides of the equation.

So, if x + 3 = 5 and you want x by itself, you’ve got to “zero out” the + 3. To make the + 3 cancel out, you’ve got to subtract 3. That means you’ll have 3 – 3 on the side with the x, and 3 – 3 is 0, and 0 is nothing. That’s what you want… nothing with the x.

But, if you want to subtract 3 from the left side, you gotta subtract 3 from the right, too, to keep ‘em equal.

x + 3 = 5
x + 3 – 3 = 5 – 3
x + 0 = 2
x = 2

Okay, that’s the easy part. Hard part is, if you got x’s on both sides.

2x = x + 5

What do I want to do? Subtract x from both sides, to get rid of the x on the right (x – x is the same as 3 – 3 or 23 – 23…. it’s zero).

2x = x + 5
2x – x = x – x + 5
2x – x = 0 + 5
2x – x = 5

Now, what’s 2x – x? The shorthand rule is, you subtract (or add) the numbers by the x’s, and leave the x alone. “x” without a number has an invisible “1″ next to it. So:
5x – 3x = 2x
22x + 5x = 7x
x + x = 2x
5x – x = 4x

That means, if 2x – x = 5, then x = 5.

Here’s why. 5x means 5 times x. And 5 times x means x + x + x + x + x. That’s what multiplication is, a shorthand way to add a number plus itself a bunch of time.
5 × 9 = 9 + 9 + 9 + 9 + 9
5x = x + x + x + x + x

So, 2x – x means x + x – x. Two of the x’s cancel out (x – x = 0). So, it’s x + 0, or just plain x.

2 x’s minus 1 x is… 1 x. Just like if you got 2 apples and take away 1 apple, you got one apple left.

So, here’s a problem:

5x + 14 = 3x + 22

I can subtract 14 from both sides to move all the numbers to the right…
5x = 3x + 8

Now, I can subtract 3x from both sides to move all the x’s to the left…
2x = 8

The last step, since x is multiplied by 2, is divide both sides by 2 to get the x by itself….

x = 4

There ya go!

Well, I figured out that respect from a bunch of gang bangers isn’t what makes you a big man. I been to prison a couple of times, and I figured out that I wasn’t going nowhere.

I can have something better than going to jail or getting shot dead one day. I’ve seen too many people killed on the streets. Gotta be a better life than this, right?

So, I got into a GED study program at The GED Academy. It’s pretty good. I’m a smart guy. I know that. So, I just gotta apply myself. I want to get my GED real fast, so I’m gonna put all my energy to getting my GED right away. I call it my Speed GED. Come check out my blog, and I’ll have some GED problems, how my progress is going, and how I’m making my plan. The GED is serious bizniz to me. So, let’s get going!

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