How to Solve Linear Equations with Reciprocals

Use the reciprocal of the number that you’re trying to “get rid of” if a fraction is multiplying the variable. Solve linear equations with reciprocals when you see a fraction — it's easier than using multiplication or division.

Here is an example of a fraction multiplying the variable:

Look at the following examples of reciprocals — after the reciprocals, you can see how each, when multiplied together, equals 1:

  • 5 and 1/5 are reciprocals:

  • −3/7and −7/3 are reciprocals:

Solving equations in the fewest possible steps is usually preferable.

Use the following steps for this example to solve for the variable, using reciprocals.

  1. 1Multiply each side by the reciprocal.

    In this example, the variable is multiplied by 4/5.

    So each side of the equation needs to be multiplied by the reciprocal 5/4.

  2. 2Reduce and simplify.

    On the left side, the 5s and 4s cancel each other out, and on the right side, 4 divides 12 by 3, resulting in:

    a = 5 × 3

    a = 15

Decimals can be made into fractions, which are much easier to deal and avoid the problem of inadvertently misplacing the decimal when performing operations.

Comments (1)

  1. Posted by Bella kell
    thiswas a messed up thing i dont get it wear is a example come on i hate this for making a stupet sight. by and plz make a better siht for me byby

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