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Solve for x and y 5x+4y=9 x+2y=3

User Michael Shum
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1 Answer

26 votes
26 votes

You have the following system of equations:


\begin{gathered} 5x+4y=9 \\ x+2y=3 \end{gathered}

In order to solve the previous equation, you first multiply by -2 the second equation:


\begin{gathered} (x+2y=3)(-2) \\ -2x-4y=-6 \end{gathered}

Next, you add the first equation of the system with the previous result:

5x + 4y = 9

-2x - 4y = -6

3x + 0 = 3

Next, you solve the previous result for x:


\begin{gathered} 3x=3 \\ x=(3)/(3)=1 \end{gathered}

Next, you replace the previous value of x into one of the equation of the system. For instance, you use:


\begin{gathered} x+2y=3 \\ 1+2y=3 \\ 2y=3-1 \\ 2y=2 \\ y=(2)/(2)=1 \end{gathered}

Hence, the solution to the given system of equations is:

x = 1

y = 1

User Hivert
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