x÷4=11
X=11x4
X=44
5x一17=73
5X=73+17
X=90÷5
X=18
6.1一x=4·5
x=6.1-4.5
x=1.6
4X+16=100
4x=100一16
x=84÷4
X=21
(x+2)÷5=6.2
x+2=6.2x5
x=31-2
X=29
4x+7x=12.1
11X=12.1
X=12.1÷11
x=1.1
5X一2.1x4=11.6
5x一8.4=11.6
5X=11.6+8.4
x=20÷5
x=4
8x一3x=3.5
5X=3.5
X=3.5÷5
X=0.7