Question

已知关于x的方程3x-2m+1=0与m=1-2x的解互为相反数,求m的值

Answer 1

3x-2m+1=0,则x=(1-2m)/3

m=1-2x,则2x=1-m,则x=(1-m)/2

解互为相反数,则(1-2m)/3+(1-m)/2=0

两边同时乘以6,得

2(1-2m)+3(1-m)=0

2-4m+3-3m=0

7m=5

m=5/7