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# Solving Rational Equations with Unlike Denominators

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When solving rational equations with unlike denominators, the first step is to factor the denominators and look for a common denominator. Next, we multiply both sides of the equation by the common denominator to clear the fractions. Finally, we solve for the variable using an appropriate technique.

Remember that solving an equation means that you're going to try to look for what the variable is equal to or what values of that variable makes your equation equality. Watch out for what we call excluded values, an excluded value is any value of the variable that would make your fraction undefined or that would make your denominator equal to zero. That's really important when you're solving rational equations. A lot of times you do all kinds of Mathy stuff and you get an answer you think you got it right but it turns out what you found was an excluded value. You always have to check at the end that your solution makes sense. Other things to be careful of are making sure you have common denominators when you're adding or subtracting fractions.

The last thing is a shortcut, if ever all of your fractions have the exact same denominator or if you can multiply things such that they have the exact same denominator those denominators can be canceled out. It's the essentially you're multiplying all of those terms by the denominator so denominators go away, then you can just work with the tops. That's a great strategy to think about when you're solving equations involving rational expressions.

One other strategy you always want to look out for is cross multiplying. If you have 2 equal fractions you can cross multiply and work through your equation that way. So good luck with this guys these are pretty difficult, they are pretty challenging but you can do it and a couple of strategies for you to keep in the back of your head are cross multiplying and clearing the denominators.

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