Question 127011
Find a constant value or values that you can multiply one or both equations by so that you will result in the coefficients on one of the variables having coefficients that are additive inverses.  Then add the two equations together, term by term, and the result will be the elimination of one of the variables.


Example:

{{{2x-y=4}}}
{{{3x-y=6}}}


You could multiply the first equation by -1 to get {{{-2x+y=-4}}} that way when you add the two equations together you get {{{1x + 0y = 2}}}, then knowing what x is, you can substitute that back into either of the equations and easily compute y.


Or, you could multiply the first equation by 3 and the second equation by -2, giving you:


{{{6x-3y=12}}} and
{{{-6x+2y=-12}}}


Adding gives you {{{0x - 1y = 0}}}, and then you can substitute this value for y to easily compute x.