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Solutions to systems (3,1)Y = 2x - 52x-5y = 1

User Cheska
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1 Answer

10 votes
10 votes

Given the equations:


\begin{gathered} 1)y=2x-5 \\ 2)2x-5y=1 \end{gathered}

To solve this equation system, you have to replace the first one into the second one:


2x-5(2x-5)=1

Solve the term in parentheses using the distributive propperty of multiplication


\begin{gathered} 2x-5\cdot2x-5\cdot(-5)=1 \\ 2x-10x+10=1 \end{gathered}

Solve for x


\begin{gathered} 2x-10x+25=1 \\ -8x=1-25 \\ -8x=-24 \\ x=-(24)/(-8) \\ x=3 \end{gathered}

Finally replace the calculated value of x in the first equation and solve for y


\begin{gathered} y=2\cdot3-5 \\ y=1 \end{gathered}

Using the second equation you can prove if the calculations are correct:


\begin{gathered} 2x-5y=1 \\ \text{for x=3 and y=1 } \\ 2\cdot3-5\cdot1=6-5=1 \end{gathered}

The calculations check, the values are x=3 and y=1

User Shady
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