4x-y=1
y=4x-1
y=2x+3
即：4x-1=2x+3
2x=4
x=2
y=4x-1=7
x=2
y=7那这个题呢？{x=1+y，x+y+z=14，x+y-2z=5x=1+y， (1)x+y+z=14，(2)x+y-2z=5 (3)将（1）代入2：1+y+y+z=14 2y+z=13 (4)将(1)代入(3)1+y+y-2z=5y-z=2y=2+z (5)将（5）代入（4）4+2z+z=13z=3y=5x=6还有最后两道题，帮忙解了吧!谢谢啊{4(x+1)=3(y+3),x-2y=-4+2x{s-1/5=t+3/2,s-1/2=1-t/24(x+1)=3(y+3),4x+4=3y+94x-3y=5 (1) x-2y=-4+2xx+2y=4 (2)(1)x2+(2)x311x=22x=2y=1 s-1/5=t+3/2, 10s=10t+17s-1/2=1-t/210s=15-5t10t+17=15-5t15t=-2t=-2/15s=3/2-1/15=43/30