Răspuns:
x=0,1,2,3,4,5;
Explicație pas cu pas:
3x+3<=19;
3x<=19-3;
3x<=16;
x<=16/3;
x<=5 rest 1;
x=0; 3*0+3<=19; 3<=19(adevarat)
x=1; 3*1+3<=19; 6<=19(adevarat);
x=2;3*2+3<=19; 9<=19(adevarat);
x=3;3*3+3<=19; 12<=19(adevarat);
x=4;4*3+3<=19;15<=19(adevarat);
x=5;5*3+3<=19; 18<=19(adevarat);