9,5х-(3,2х+1,8х)+3,75=6,9
1)3.2х+1.8х=5х
2)9.5х-5х=4.5х
4.5х+3.75=6.9
4.5х=6.9-3.75
4.5х=3.15
х=3.15:4.5
х=0.7