$\left \{ {{2x + y = 1} \atop {3x - 2y = 12}} \right.$
⇔$\left \{ {{6x + 3y = 3} \atop {6x - 4y = 24}} \right.$
⇔$\left \{ {{6x - 4y - 6x - 3y = 21} \atop {6x+3y=3}} \right.$
⇔$\left \{ {{-7y=21} \atop {6x+3y=3}} \right.$
⇔$\left \{ {{y=-3} \atop {6x-9=3}} \right.$
⇔$\left \{ {{y=-3} \atop {x=2}} \right.$
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