(x-40)-[1/4(x-40)+1/3(x-40)]+40=(1/2)x怎么解

问题描述:

(x-40)-[1/4(x-40)+1/3(x-40)]+40=(1/2)x怎么解

(x-40)-[1/4(x-40)+1/3(x-40)]+40=(1/2)x{(x-40)-[1/4(x-40)+1/3(x-40)]+40}*2=x2x-80-(1/2)(x-40)-(1/3)(2x-80)+80=xx-(1/2)(x-40)-(1/3)(2x-80)=0(1/6)(6x-3x+120-4x+160)=0(1/6)(280-x)=0280-x=0x=280