Solving linear equations is one of the most fundamental skills an algebra student can master. Most algebraic equations require the skills used when solving linear equations. This fact makes it essential that the algebra student becomes proficient in solving these problems. By using the same process over and over, you can solve any linear equation that your math teacher sends your way.
A Simple Example
Start by moving all of the terms that contain a variable to the left-hand side of the equation. For example, if you are solving
you will move the 3a to the left-hand side of the equation. To do this, you must add the opposite of 3a to both sides. When you add −3a to both sides, you get
Move the terms that do not contain variables to the right-hand side of the equation. In this example, you will add the opposite of +16 to both sides. This is −16, so you will have
This gives you
Look at the variable (a) and determine if there are any other operations being performed on it. In this example, it is being multiplied by 2. Do the opposite operation, which is dividing by 2. This gives you
which simplifies to
Check your answer for accuracy. To do this, put the answer back in to the original equation.
This gives you
This is true, because 31 = 31.
A More Complex Example
Use the same process, even if the equation contains negatives or fractions. For instance, if you are solving
you would begin by moving the 2x to the left-hand side of the equation. This requires you to add the opposite. Since you will be adding it to a fraction (5/4), change the 2 to a fraction with a common denominator (8/4). Add the opposite:
which gives
Move the + 1/2 to the right-hand side of the equation. To do this, add the opposite ( −1/2). This gives
which simplifies to
Divide both sides by −3/4. To divide by a fraction, you must multiply by the reciprocal ( −4/3). This gives
which simplifies to
Check your answer. To do this, plug 4/3 in to the original equation.
This gives
This is true, because 13/6 = 13/6.
For another example, view the video below:
Tip: Using a calculator actually makes solving linear equations longer. If possible, do this work by hand, especially when working with fractions.
Warning: Always check your answer. Making mistakes along the way is quite easy when solving linear equations. Checking your answers will ensure that you do not get the problem wrong.
Tips
- Using a calculator actually makes solving linear equations longer. If possible, do this work by hand, especially when working with fractions.
Warnings
- Always check your answer. Making mistakes along the way is quite easy when solving linear equations. Checking your answers will ensure that you do not get the problem wrong.
About the Author
Nicole Harms has been writing professionally since 2006, specializing in real estate, finance and travel. When she's not writing, she enjoys traveling and has visited several countries, including Israel, Spain, France and Guam. Harms received a Bachelor of Science in Education from Maranatha Baptist Bible College.