(1)方程(I)整理后得到：x+y=3m/2.(iii)
把(iii)与方程(ii)相加得,
2x=11m/2+1
x=11m/4+1/2
把上式代入方程(iii),解得,y=-5m/4-1/2
(2)x>0,11m/4+1/2>0,m>-2/11
y>0,-5m/4-1/2>0,m