Răspuns :
3.4x=17
x=17/3.4
x=5
verificare.
5+1.2×5+1.2×5+2=19
5+6+6+2=19
17+2=19
19=19 A
x=17/3.4
x=5
verificare.
5+1.2×5+1.2×5+2=19
5+6+6+2=19
17+2=19
19=19 A
x+1,2x+1,2x+2=19
x+1,2x+1,2x=19-2
x+1,2x+1,2x=17
x+2,4x=17
3,4x=17
x=17:3,4
x=5
x+1,2x+1,2x=19-2
x+1,2x+1,2x=17
x+2,4x=17
3,4x=17
x=17:3,4
x=5