[40x+35.5*(8-x)+3*36]/11=38.5
解:[40x+284-35.5x+108]/11=38.5
[4.5x+392]/11=38.5
[4.5x+392]/11*11=38.5*11
4.5x+392=423.5
4.5x=31.5
x=7
(40x+35.5*(8-x)+3*36]÷11=38.5
40x+284-35.5x+108=423.5
40x-35.5x=423.5-108-284
4.5x=31.5
x=31.5÷4.5
x=7
不懂可追问!
解:40X+35.5*8-35.5X+3*36=38.5*11
4.5X=38.5*11-38.5*8-3*36
4.5X=38.5*3-3*36
4.5X=2.5*3
X=7.5/4.5
X=5/3
40X+284-35.5X+108=38.5*11
4.5X=423.5-284
4.5X=139.5
X=31
[40x+35.5*(8-x)+3*36]÷11=38.5
40x+284-35.5x+108=423.5
40x-35.5x=423.5-108-284
4.5x=31.5
x=31.5÷4.5
x=7