1 . Dati factor comun in urmatoarele expresii : 5·x+17·x =
6·a-18·b =
3·a+18·b-12·c =

2 . Daca x+y+z=17 , calculati :
5·x+5·y+5·z =
13·x+13·y+13·z-1313 =
882-3·(7·x+7·y+ 7·z) =