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Oliver
07-11-2013, 05:06 PM
SAT simultaneous equations

How can we solve the following system of equations:

\begin{cases} 4x+ 2y=8 \\ x + y=3 \end{cases}

07-11-2013, 05:18 PM
SAT math simultaneous equations

\begin{cases} 4x+ 2y=8 \\ x + y=3 \end{cases}

The method of elimination or addition (step-by-step) is:

In the elimination method, the object is to make the coefficients of one variable the same in both equations so that one variable can be eliminated either by adding the equations together or by subtracting one from the other.

\begin{cases} 4x+ 2y=8 \\ -4x -4y=-4(3) \end{cases} Multiply by -4

\begin{cases} 4x+ 2y=8 \\ -4x -4y=-12 \end{cases} Add equations

\begin{cases} -2y=-4 \\ x=3-y \end{cases}

\begin{cases} y=2 \\ x=3-2=1 \end{cases}

Hope these help!!:D:D

Oliver
07-11-2013, 05:18 PM