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A system of equations is given below.x + 2y = 24x − 5y = 8Identify the constant that can be multiplied by both sides of the first equation to eliminate the variable x when the equations are added together.thenWrite the revised system of equations.

User Alvin Rusli
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1 Answer

21 votes
21 votes

Answer:


constant\rightarrow-4

Step-by-step explanation: We have to find the constant that when multiplied to the first equation and added to the second, the variable x gets canceled out, the two equations are as follows:


\begin{gathered} x+2y=2\rightarrow(1) \\ 4x-5y=8\rightarrow(2) \end{gathered}

Multiplying the equation (1) by -4 and adding it to the equation (2) gives the following answer:


\begin{gathered} -4*(x+2y)=-4*2\rightarrow-4x-8y=-8 \\ \begin{equation*} -4x-8y=-8 \end{equation*} \\ + \\ \begin{equation*} 4x-5y=8 \end{equation*} \\ ---------------------- \\ -3y=0 \end{gathered}

Therefore the value of the constant is -4.

User Akayh
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