## Appendix A. Leftovers: The Top Five Things (we didn’t cover)

### Note

Yes, just five. You’ve learned so much already...

You’ve learned a lot in this book, but Algebra has even more to offer. Don’t worry, we’re almost done! Before we go, there are just a few gaps we want to fill in. Then you’ll be onto Algebra 2, and that’s a whole additional book...

## #1 Negative Exponents

We touched on them in Chapter 3, but as a quick refresher, here’s what a negative exponent looks like:

Combine that rule with multiplying exponential terms, and you can divide exponential terms too, like this:

What’s going on here? It’s really a matter of cancelling things out... here’s a simple example, where you can see the cancelling in action:

A negative exponent means that you divide one by the exponential term, with its exponent stripped of its negative sign. Negative exponents are a great way to get rid of fractions. Any fraction can be rewritten as a negative exponent, and you can work with it the same way you would work with any other exponent.

Negative exponents mean you can get rid of fractions.

## Working with negative exponents ...

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