# Section 7.1&2 – Systems of Equations

Section Details.
• Solving a linear system with two equations
• The graphical interpretation of a system of linear equations
• Using the substitution method to solve a linear system of equations
• Using the elimination method to solve a linear system of equations

### Practice Problems

Directions. The following are review problems for the section. We recommend you work the problems yourself, and then click "Answer" to check your answer. If you do not understand a problem, you can click "Video" to learn how to solve it.
1.  Solve using substitution:
\begin{array}{c}
x + 5 y = 47\\
7x-8y=-15
\end{array}

$$\left(\dfrac{301}{43},\dfrac{344}{43}\right)$$

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2. Solve using elimination:\begin{array}{c}
4x-5y=8\\
-8x+10y = -16
\end{array} ​

$$\left(a,-\dfrac{8}{5}+\dfrac{4}{5}a\right)$$

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3. Solve using whichever method you choose: \begin{array}{c}
3x-9y=11\\
-4x+12y = 0
\end{array}

No Solution

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