1]
[tex]3e-9-6e=9\\\\3e-6e=9+9\\\\-3e=18 \ \ |:(-3)\\\\\boxed{e=-6}[/tex]
2]
[tex]5f-3-f=4\\\\5f-f=4+3\\\\4f=7 \ \ |:4\\\\\boxed{f=1,75}[/tex]
