1)(x+5,3):9=2,04
х+5.3=2.04*9
х+5.3=18.36
х=18.36-5.3
х=13.06
2)26,2-5*x=17,4
5х=26.2-17.4
5х=8.8
х=8.8:5
х=1.76
3)40,32:(406,2-x)=2,1
406.2-х=40.32:2.1
406.2-х=19.2
х=406.2-19.2
х=387
4)2,6*x+7.6*x-0,06=4,02
10.2х=4.02+0.06
10.2х=4.08
х=4.08:10.2
х=0.4