**Solving One-Step Equations**

It does not matter which textbook your school has chosen to use, nor does it really matter the age of the text. Solving multi-step equations will be apart of what you have learned. I work with Prentice Hall's Algebra 1 (2009) and in the years before that I worked with Glencoe's Algebra 1 (1999). I tell you what books I have used because that should give you a clear picture that solving equations is an important part algebra and learning how to solve one-step equations is the building block to solving two-step and multi-step equations. Remember, the goal of solving multi-step equations is to isolate the variable correctly to get the answer.

Isolating the Variable

Example 1 |

**with a value equal to -6. From this example, I hope you understand how I will tie the examples into what I am blogging about. Please notice how I use numbers next to the equations.**

*now isolated*Solving One Step Equations with Addition and Subtraction

Example 2 |

Example 2 is another equation in which the focus can be on the operation between the variable and the number.

*The focus can be on the the sign between the number and variable when the number is positive*. As in example 2, since 6 is added to the variable, to get rid of the 6, it is subtracted from the 6 on the left and it is subtracted from the right to maintain the balance of the equation. Because the 6 and -6 on the left are opposites, those numbers combine to give 0 and the variable is isolated. Another way teachers will describe what happens on the left is to say "the 6's cancel".

Example 3 |

Addition is Subtraction and Subtraction is Addition

What? This topic can be be very confusing if you are unaware of two facts:

- Adding a negative number is the same as subtracting a positive number
- Subtracting a negative number is the same as adding positive number

Example 4 Incorrect and Correct Way To Solve an Equation |

Example 5 |

If it is obvious to you that you need to add to solve this equation, then rewriting the equation as equation 2 is not necessary to find the correct solution.

Example 6 |

The final example, rule #2 is illustrated. Equation 1 is x - (-5) = 7. Notice the "double negative" between the variable and the number. Some teachers, including will say, "a double negative makes a positive." We say that because it does and it offers an easy way to remember rule number 2. After using rule #2, the equation can be solve by subtracting 5 from both sides. This isolates the variable and gives x = 2.

Using the below video will give you some interactive practice with solving one-step equations with addition and subtraction.

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