# Algebrarules.com

The most useful rules of basic algebra,
free, simple, & intuitively organized
X

Howdy! Here are a few very handy rules of algebra. These basic rules are useful for everything from figuring out your gas mileage to acing your next math test — or even solving equations from the far reaches of theoretical physics. Happy calculating!

## Algebra Rule 8

#### Fractions with common denominators can be combined

$${(a+b) \over c} = {a \over c} + {b \over c}$$
Description:

Two fractions with common denominators can be added by adding the numerators and leaving the denominator unchanged. Going the other direction, we can also break apart a fraction with an addition in the numerator into two fractions (each with the common denominator).

$${(1+2) \over 4} = {3 \over 4} = {1 \over 4} + {2 \over 4}$$
« Previous Rule Next Rule »

## A little bit about algebrarules.com

Algebra rules is a project by two of the folks who run The Autodidacts.

A couple of autodidact math enthusiasts, we were looking for all the rules of basic algebra concisely presented in one place. We couldn’t find such a place, so we made Algebrarules.com

These simple rules — applied with a pinch of imagination and a dash of arithmetic — can divide, conquer, and solve just about any practical algebra problem.

If you find errata in the math, bugs in the code of Algebrarules.com, or just want to say Eh, please send us a letter or join us on our roost: @rulesofalgebra.

## Support algebrarules.com

You've made it all the way to the end! If you found this site useful, pay it forward by helping us help more people learn algebra!