1.4 Solving Equations

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1.4 Solving Equations
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Review of Terms

• A variable is a letter which represents an
  unknown number. Any letter can be used as a
  variable.
• An algebraic expression contains at least one
  variable.
• Examples a, x5, 3y 2z
• A verbal expression uses words to translate
  algebraic expressions.
• Example The sum of a number and 3 represents
  n3.

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• An equation is a sentence that states that two
  mathematical expressions are equal.
• Example 2x-1618

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Steps to Solving Equations

• Simplify each side of the equation, if needed, by
  distributing or combining like terms.
• Move variables to one side of the equation by
  using the opposite operation of addition or
  subtraction.
• Isolate the variable by applying the opposite
  operation to each side.
• First, use the opposite operation of addition or
  subtraction.
• Second, use the opposite operation of
  multiplication or division.
• Check your answer.

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Examples

• y is the variable.
• Add 6 to each side to isolate the variable.
• Now divide both sides by 3.
• The answer is 5.
• Check the answer by substituting it into the
  original equation.

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Try this. . .

• Did you get x - 4?
• You were right!