1)(x-2y)(x-3y)=0
所以x=2y
或x=3y
y:x=1/2或1/3
2）设a,b是另两边
则a+b=6
ab=m/2
是三角形两边
则要满足a+b>5且a-b0
(a-b)^2=(a+b)^2-4ab=36-2m0
又△=144-8m≥0
综上得5.5