1/3-M-1/2=1/9-2M+ +1/团好陵4-1/6-M =13/36-2M+ -1/塌戚6 =13/袜胡36-3M+0 =19/36-3M+《3M-19/36》OK啦,一定要选我呦!!
-1/3m
x=2m/9-5/4