In order to simplify complex variables, you must first consider the numerical values separate from the variable. In the case of 24x/48x, you would look at the numbers alone to see if they have any factors. These numbers have the number 6 in common. So, divide it by 6. This will give you 4/8. This still requires some simplification. Two is still a factor for both. So, divide it again by four. This will give you 1/2. Now, if the numerator was raised to the second power, in the original equation, and the denominator was raised to the fourth power, then, you can use cancelation to simplify them. xx/xxxx. If you use cancelation, this will leave you with 1/xx or one over x squared.