36.8-X=15.6
-x=15.6-36.8
x=21.22.85-0.4x=1解方程2.85-0.4x=12.85-1=0.4x0.4x=1.854x=18.5x=4.62512X-8X=7.2解方程12X-8X=7.24x=7.2x=1.8