2,5(3x+16)-5(2,2x+3,4)=5(2,6-0,3x)

2.5(3х+16)-5(2.2х+3.4)=5(2.6-0.3х)=

=7.5х+40-5(22х+3,4)=5(2,6-0,3х)=

7,5х+40-5-11х-17=5(2,6-0,3х)

7,5х+40-5-11х-17=13-1,5х

-3,5х+40-17=13-1,5х

-3,5х+23=13-1,5х

-3,5х+23+1,5х=13

-3,5х+1,5х=13-23

-2х=13-23

-2х=-10

х=5

надеюсь понятно написала....