## SOLVING LINEAR EQUATIONS

Recall the following:

• A linear equation is a polynomial of degree 1.

• In order to solve for the unknown variable, you must isolate the variable.

• In the order of operations, multiplication and division are completed before addition and subtraction.

Example 3: Solve for x in the following equation.

Multiply both sides by the lowest common multiple of 3, 6, 9, and 18, or 18.

Simplify:

Subtract 10x from both sides of the equation:

Subtract 15 from both sides of the equation:

Divide both sides by 2:

Check the solution by substituting 4 in the original equation for x. If the left side of the equation equals the right side of the equation after the substitution, you have found the correct answer.

• Left side:
• Right Side:
• Left Side:
• Right Side:
You can also check your answer by graphing (left side of the original equation minus the right side of the original equation). The graph will cross the x-axis at x=3.5.

### If you would like to test yourself by working some problems similar to this example, click on Problem

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