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Chapter 8 Vocabulary Check


        Fill in each blank with one of the words or phrases listed below.
           variable    addition     constant               algebraic expression      equation

           terms       simplified    multiplication         evaluating the expression  solution
           like        combined     numerical coefficient   distributive
         1. An algebraic expression is                        9. A(n)                        is of the form
           when all like terms have been                        expression =  expression.
                                   .                         10. A(n)                        of an equation is a
         2. Terms that are exactly the same, except that they may  value for the variable that makes the equation a true
           have different numerical coefficients, are called     statement.
                                    terms.                   11. To multiply -3(2x + 1) , we use the
         3. A letter used to represent a number is called a(n)                           property.
                                   .                         12. By the                        property of
         4. A combination of operations on variables and        equality, we may multiply or divide both sides of an
           numbers is called a(n)                      .        equation by any nonzero number without changing
         5. The addends of an algebraic expression are called the  the solution of the equation.
                                    of the expression.       13. By the                        property of equal-
         6. The number factor of a variable term is called the  ity, the same number may be added to or subtracted
                                   .                            from both sides of an equation without changing the
                                                                solution of the equation.
         7. Replacing a variable in an expression by a number
           and then finding the value of the expression is called
                                    for the variable.
         8. A term that is a number only is called a(n)                             Are you preparing for your
                                   .                                 test? Don’t forget to take the Chapter 8 Test on
                                                                     page 614. Then check your answers at the back
                                                                     of the text and use the Chapter  Test Prep
                                                                     Videos to see the fully worked-out solutions to
         8       Chapter Highlights                                  any of the exercises you want to review.



                   Definitions and Concepts                                      Examples

                                            Section 8.1  Variable Expressions

        A letter used to represent a number is called a variable.  x, y, z, a, b
        A combination of numbers, letters (variables), and operation  3 + x, 7y, x + y - 10
                                                                            3
         symbols is called an algebraic expression, or expression.
        Replacing a variable in an expression by a number and  Evaluate: 2x + y  when x = 22  and y = 4
         then finding the value of the expression is called
                                                                             #
                                                                    2x + y = 2 22 + 4  Replace x with 22 and y with 4.
         evaluating the expression.
                                                                           = 44 + 4    Multiply.
                                                                           = 48        Add.
        The addends of an algebraic expression are called the        2
         terms of the expression.                                 5x +(–4x)+(–2)
                                                                                       3 terms
        The number factor of a variable term is called the       Term        Numerical Coefficient
         numerical coefficient.                                     7x                 7
                                                                  -6y                -6
        Terms that are exactly the same, except that they may
                                                                 x or 1x              1
         have different numerical coefficients, are called like     5x + 11x = 15 + 112x = 16x
         terms.                                                                                                     Copyright 2012 Pearson Education, Inc.
                                                                    a   Q
        An algebraic expression is simplified when all like terms   like terms
         have been combined.                                        b  R
                                                                   y - 6y = 11 - 62y =-5y

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