①如果|x+2y-1|+|2x+y-5|=0.则x+y的值是______;②已知: x=2+3t y=4-t

2025-05-09 05:51:30
推荐回答(1个)
回答1:

①∵|x+2y-1|+|2x+y-5|=0,
x+2y-1=0(1)
2x+y-5=0(2)

∴(1)+(2)得,3x+3y-6=0,
即x+y=2.
故答案为2;
x=2+3t(1)
y=4-t(2)

由(2)得,t=4-y(3),
将(3)代入(1)得,x=2+3(4-y),
整理得,x+3y=14.
故答案为x+3y=14.