2(x+y)-(x-y)=4 3(x-2y)+4(x+y)=5 x+y=9 3x-2y=12

2(x+y)-(x-y)=4 3(x-2y)+4(x+y)=5 2x + 2y -x +y =4 3x-6y+4x+4y=5 x+3y=4 7x-2y=5 x=4-3y x=4-3×1 7(4-3y)-2y=5 x=4-6=-2 28-21y-2y=5 -23y=-23 /÷-23 y=1 x+y=9 / ×(-3) x=9-y 3x-2y=12 x=9-3 x=6 -3x+-3y=-27 / 3x-2y=12 / -5y =-15 /÷(-5) y=3