2x+y=2+3m,x+2y=1-m相加3x+3y=3+2mx+y>0则3x+3y>0所以3+2m>0m>-3/2
两式连列,相加得3x+3y=3+2m,这个式子除以3,得x+y=1+2m/3,又因为x+y大于0,得1+2m/3大于0,求解,m小于3/2