4[2X+Y]-5[2X-Y]=3,8x+4y-10x+5y=3,2x-9y=-3
X+1=5[y+2],x+1-5y-10=0,x-5y=9,2x-10y=18
y=-21
x=9+5y=9-105=-96
2[2X+Y]=10[2X-Y]=39为什么两个等号?
3[2x-5]-4[3y+4]=5
4[2X+Y]-5[2X-Y]=3,8x+4y-10x+5y=3,2x-9y=-3
X+1=5[y+2],x+1-5y-10=0,x-5y=9,2x-10y=18
y=-21
x=9+5y=9-105=-96
2[2X+Y]=10[2X-Y]=39为什么两个等号?
3[2x-5]-4[3y+4]=5