(5m-1)/(2m-3)+(7-m)/2=5(2m-3)(7-m)+10m-2=10(2m-3)10m-2+14m-21-2m²+3m=20m-3010m-2m²-23=20m-307m-2m²+7=02m²-7m-7=0m²-7/2m-7/2=0解得：m=（7+√105）/4或 m=(7-√105）／4
