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{2-5(0.2y-2x)=3(3x+3)+y ⇒{2-y+10x=9x+9+y ⇒{10x-9x-y-y=9-2⇒
{x-2y=7;⇒x=7+2y;
{4(x-2y)-(2x-y)=2-2(2x+y) ⇒{4x-8y-2x+y=2-4x-2y⇒{4x-2x+4x-8y+y+2y=2⇒
{6x-5y=2;
6(7+2y)-5y=2;⇒42+12y-5y=2;⇒7y=-40;
y=-40/7=-5⁵/₇;
x=7+2(-40/7)=7-80/7=7-11³/₇=-4³/₇;