Linear Algebra For Dummies
Book image
Explore Book Buy On Amazon

Often, you need to use both multiplication and division to solve a linear equation. When a linear equation uses both multiplication and division, you solve by using the inverse operation of each. So, if a variable is both multiplied and divided by a number in an equation, you solve the equation for that variable by using a combination of multiplication and division.

Example:

image0.png

Apply these steps to solve an equation with multiplication and division by trying to solve for a.

  1. Determine the value that divides the variable.

    In this case, the 5 is dividing into both the 4 and the variable.

  2. Multiply the values on each side of the equal sign.

    image1.png
  3. Reduce and simplify.

    The 5 cancels itself out on the left side of the equation, leaving you with

    4a = 12(5)

    4a = 60

  4. Determine what is multiplying the variable.

    The number 4 is the coefficient and multiplies the a.

  5. Divide the values on each side of the equal sign.

    image2.png
  6. Reduce and simplify.

    The 4 cancels itself out on the left side of the equation, leaving you with

    image3.png

About This Article

This article is from the book:

About the book author:

Mary Jane Sterling taught algebra, business calculus, geometry, and finite mathematics at Bradley University in Peoria, Illinois, for more than 30 years. She is the author of several For Dummies books, including Algebra Workbook For Dummies, Algebra II For Dummies, and Algebra II Workbook For Dummies.

This article can be found in the category: