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I need to substitute to solve each system of equations then, put in an a pair like this: ( )

I need to substitute to solve each system of equations then, put in an a pair like-example-1
User Besa
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1 Answer

27 votes
27 votes

System of Equations

Given the equations:


\begin{cases}y=4x-1 \\ y=2x-5\end{cases}

Solve it by substitution.

Since the y is isolated in both equations, we just substitute one into the other equation as follows:


2x-5=4x-1

Adding 5 and subtracting 4x:


\begin{gathered} 2x-4x=-1+5 \\ \text{Simplifying:} \\ -2x=4 \\ \text{Dividing by -2:} \\ x=-2 \end{gathered}

To find the value of y, just substitute x = -2 in any of the equations:


\begin{gathered} y=4(-2)-1 \\ y=-8-1 \\ y=-9 \end{gathered}

If we had used the second equation, we would have gotten the very same result.

Answer: (-2, -9)

User Farhat
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