0.8X*(0.5+0.4)=4.32 0.72x=4.32x=6x-2分x+1=2+2分x+1(x+1)/(x-2)=2+(x+1)/22x+2=4(x-2)+(x+1)(x-2)x^2-x-2+4x-8-2x-2=0x^2+x-12=0(x+4)(x-3)=0x=-4或3
x=4.32/0.72=6
0.8X*(0.5+0.4)=4.32 0.8x*0.9=4.320.8x=4.8x=6