Solve these simultaneous equations, 2x+y=6 and 3y-x=11
First step is to choose between the three methods for solving simulataneous equations; elimination, substitution and eqaulity. In this case the best method is probably substitution, but personal preference is reasonable. By rearranging the second equation to find an expression for x we get; x=3y-11. Substituting this into the first equation gives 2(3y-11)+y= 6y-22+y=7y-22=6. Add 22 to both sides for 7y=28 and hence by dividing both sides by 7, we obtain y=4. Substitute this into either equation and solve, eg, 2x+4=6 gives x=1. Therefore the solution is x=1 and y=4.
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