Clasa V-a
ex. 4 / pag. 33

Explicație pas cu pas:
ab+ac
a(b+c)2.50=100
xy+xz+15
x(y+z)+15
9.11+15=114
ab-ac
a(b-c)
7.100=700
5xy+5xz+21
54y+54z+21
54(y+z)+21
54.100+21=5421