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-3x+8y=73x-7y=-46 Directions: Solve each system of equations by elimination. Clearly identify your solution.

User Jcgiret
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1 Answer

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\begin{gathered} \text{Let:} \\ -3x+8y=73\text{ (1)} \\ x-7y=-46\text{ (2)} \end{gathered}

Multiply (2) by 3:

3x - 21y = -138

Add (1) and (2):


\begin{gathered} (-3x+8y=73)/(3x-21y=-138)\text{ +} \\ \\ -13y=-65 \end{gathered}

Solving for y:

Divide both sides by -13:


\begin{gathered} (-13y)/(-13)=(-65)/(-13) \\ y=5 \end{gathered}

Replace the value of y into (2):


\begin{gathered} x-7(5)=-46 \\ x-35=-46 \\ \text{solve for x:} \\ x=-46+35 \\ x=-11 \end{gathered}

Therefore, x = -11 and y = 5

User Oleh  Sobchuk
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