1) {4y-x=11
{6y-2x=13
2) {2x +3y=16
{3X-2Y=11

1) {4y-x=11{6y-2x=13-x=11-4y6y-2x=13x=4y-116y-2(4y-11)=13x=4y-116y-8y+22=13x=4y-11-2y=13-22x=4×4.5-11y=4.5x=7y=4.52) {2x +3y=16{3X-2Y=112x=16-3y => x=(16-3y)23×(16-3y)/2-2y=11 => (48-9y)/2=11+2y => 48-9y=2×(11+2y) => -9y-4y=22-48 =>-13y= -26 => y=2x=(16-3×2)/2=5