a)2 ori x + 3 = 9 => 2 ori x = 9-3 => 2 ori x = 6 => x = 6 : 3 => x=2
b)3+5 ori x = 83 => 5 ori x = 83-3 => 5 ori x = 80 => x = 80 : 5 => x =16
c)4ori x - 6 = 18 => 4ori x = 18+6 => 4ori x=24 => x = 24 : 4 => x = 6
d) 7-3ori x =1 => 7 - 1 = 3 ori x => 6 = 3ori x=> x = 6 : 3 => x =2
e) (13+x):5 = 15 => 13+x = 15 ori 5 => 13+x= 75 => x = 75-13=> x= 62
f)72:(x-2)=9 = > x-2 = 72 : 9 => x-2 = 8 => x = 8+2 => x =10