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solve the system of equations below algebraically. state the solution as an ordered pair. Show all work.

solve the system of equations below algebraically. state the solution as an ordered-example-1
User Tim Park
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1 Answer

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We have a system of equations:


\begin{gathered} x+9=y \\ x=4y-6 \end{gathered}

We can solve it by substitution, using the equality of the first equation, replacing y in the second equation:


\begin{gathered} x=4y-6 \\ x=4(x+9)-6 \\ x=4x+4\cdot9-6 \\ x=4x+36-6 \\ x=4x+30 \\ x-4x=30 \\ -3x=30 \\ x=-(30)/(3) \\ x=-10 \end{gathered}

With the value of x, we can calculate y as:


y=x+9=-10+9=-1

The solution expressed as ordered pair is (x,y) = (-10,-1).

Answer: (-10, -1)

User Dave Cohen
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