Question

m为何值时，代数式2m-3分之5m-1的值与代数式2分之7-m的值的和等于5？

Answer 1

(5m-1)/(2m-3)+(7-m)/2=5等式两边同时乘以2(2m-3)得：2（5m-1)+(7-m)(2m-3)=10(2m-3)10m-2+14m-21-2m^2+3m=20m-302m^2-7m-7=02(m^2-7/2 m)=72(m-7/4)^2=7+49/82(m-7/4)^2=105/8(m-7/4)^2=105/16m-7/4=+/-√105/4m=7/4+/-√105/4m1=(7+√105)/4, m2=(7-√105)/4

Answer 2

(5m-1)/(2m-3)+(7-m)/2=510m-2+(7-m)(2m-3)=10(2m-3)2m�0�5-7m-7=0m=(7±√105)/4所以当m=(7+√105)/4或者m=(7-√105)/4

Answer 3

有两个解！