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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

Solve each system by addition.

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

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

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#### Solution Preview

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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