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Y= 2x – 15y = 5x Solve the system by using the substitution method

User Soorena Aban
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1 Answer

22 votes
22 votes

Substituting the second equation in the first one, we get:


5x=2x-15.

Subtracting 2x from the above equation we get:


\begin{gathered} 5x-2x=2x-15-2x, \\ 3x=-15. \end{gathered}

Dividing by 3, we get:


\begin{gathered} (3x)/(3)=-(15)/(3), \\ x=-5. \end{gathered}

Substituting the above result in the second equation of the system, we get:


\begin{gathered} y=5\cdot(-5), \\ y=-25. \end{gathered}

Answer:


\begin{gathered} x=-5, \\ y=-25. \end{gathered}

User Christer Carlsund
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