Solve the simultaneous equations 2x - 3y = 7 and 3x + 4y = 2. Do not use trail and improvement.
[ 2x - 3y = 7 ] *3 = [ 6x - 9y = 21 ]
[ 3x + 4y = 2 ] *2 = [ 6x + 8y = 4 ]
[ 6x + 8y = 4 ] - [ 6x - 9y = 21 ] = [ 17y = -17 ]
Therefore, y = -1.
Substituting y = -1 into the original equations and solving for x we get the following.
2x + 3 = 7
2x = 4
x = 2
And,
3x - 4 = 2
3x = 6
x = 2
So we have x = 2 and y = -1.
EH
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