How to Find Equivalent Expressions

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Algebra strikes fear in the hearts of many both grown and still in school. Finding equivalent expressions is not as complicated or as daunting as you might think. It comes down to taking the distributive property and working with it to find another way to say the same thing, mathematically.

Using Distributive Property

    Start with an algebraic expression. Using the example 2x(3y + 2) will make it easier to walk through the process.

    Distribute the multiple 2x throughout the rest of the equation. This means multiplying 2x by 3y and by 2. Multiply 2x and 3y and you get 6xy. Multiply 2x by 2 and you get 4x.

    Complete the equation by putting it back together. This means taking the two new numbers and keeping the function in the middle the same: 6xy + 4x. This is your equivalent expression. You can write the two expressions to show equality: 2x(3y + 2) = 6xy + 4x.

Using Factoring

    Identify the common factors in the parts of the equation. Breaking down the equation might be necessary to find an equivalent expression. If you were given the expression 6xy + 4x, you would need to work it the other direction by taking out the common numbers. In this case both numbers are divisible by 2.

    Take out the first common number: 2(3xy + 2x). Now you see there is still another common factor, x.

    Take out additional common factors: 2x(3y + 2). This gives you the equivalent expression. Again you end with 6xy + 4x = 2x(3y + 2).

    Things You'll Need

    • Paper
    • Pencil

    Tips

    • You can work equivalent expressions by distribution or factoring depending on what type of equation you are given first. If you factor to get an expression, redistribute to make sure you worked the problem correctly. If you distributed, re-factor to check your work.

    Warnings

    • Double-check your work. Sometimes symbols can get turned around, especially when dealing with negatives.

References

About the Author

Pharaba Witt has worked as a writer in Los Angeles for more than 10 years. She has written for websites such as USA Today, Red Beacon, LIVESTRONG, WiseGeek, Web Series Network, Nursing Daily and major film studios. When not traveling she enjoys outdoor activities such as backpacking, snowboarding, ice climbing and scuba diving. She is constantly researching equipment and seeking new challenges.

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