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put this solution on YOUR website!2x + (k-1)y =6 ........eq1
3x + (2k+1)y =9 ........eq2
Multiply eq1 by 3 and eq2 by 2 and subtract
6x + 3(k-1)y = 18
-6x - 2(2k+1)y = -18
3(k-1)y - 2(2k+1)y = 0
y(3(k-1) - 2(2k+1)) = 0
3(k-1) - 2(2k+1) = 0
3k - 3 - 4k - 2 = 0
-k -5 = 0
-k = 5
k = -5