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    Solving Systems of Linear Equations of Books and Magazines

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    Systems of linear equations

    Books and magazines. At Gwen's garage sale, all books were one price, and all magazines were another price.
    Harriet bought four books and three magazines for $1.45,and June bought two books and five magazines for $1.25.
    What was the price of a book and what was the price of a magazine?

    Solving by Substitution

    Solve each system by substitution. Determine whether the equations are independent, dependent, or inconsistent.

    y=-3x+19
    y=2x-1

    y=-4x-7
    y=3x

    y=x+4
    3y-5x=6

    The Addition Method
    Solve each system by addition.

    x-2y=-1
    -x+5y=4

    3x-5y=-11
    x-2y=11

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    https://brainmass.com/math/linear-algebra/solving-systems-linear-equations-books-magazines-215965

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    Solutions:

    Books and magazines. At Gwen's garage sale, all books were one price, and all magazines were another price.
    Harriet bought four books and three magazines for $1.45,and June bought two books and five magazines for $1.25.
    What was the price of a book and what was the price of a magazine?

    Let price of each book =x
    Price of each magazine=y
    Harriet bought four books and three magazines for $1.45,
    4x+3y=1.45 ---------------(1)

    June bought two books and five magazines for $1.25.
    2x+5y=1.25 ---------------(2)

    Multiply equation (2) by -2, we get
    -4x-10y=-2.5 ------------(3)

    Adding equation (1) and equation (3), we get
    4x+3y=1.45
    -4x-10y=-2.5
    -7y=-1.05
    y=0.15

    Put value of y=0.15 in equation (1), we ...

    Solution Summary

    There are 6 problems. Solutions to these problems explain the steps for finding the values of variables by Addition and Substitution method.

    $2.19