求解几道方程.1/2x-20+1/2【x-(1/2x-20)】+20=x-50 x/(200-400/3)+x/(200+400/3)=7 又12/60
问题描述:
求解几道方程.1/2x-20+1/2【x-(1/2x-20)】+20=x-50 x/(200-400/3)+x/(200+400/3)=7 又12/60
答
1/2x-20+1/2【x-(1/2x-20)】+20=x-501/2【x-(1/2x-20)】=1/2x-50 x-(1/2x-20)=x-100 1/2x-20=1001/2x=120x=240x/(200-400/3)+x/(200+400/3)=7 又12/60 3x/200+3x/1000=7.2x/200+x/1000=2.4x/250=2.4x=600...