Question

3+3×[3+3×(3+3×3)]=(3×a+3)×3+3 va rogggg e nr necunoscut!!! URGENT

Answer 1

3+3×[3+3×(3+3×3)]=(3×a+3)×3+3
3+3x(3+3x12)=(3a+3)x3+3
3+3x(3+36)=(3×a+3)×3+3
3+3x39=(3×a+3)×3+3
3+117=(3×a+3)×3+3
120=(3×a+3)×3+3
sau
(3×a+3)×3+3=120
(3xa+3)x3=120-3
3xa+3=117:3
3xa+3=39
3xa=39-3
3xa=36
a=36:3
a=12   am folosit metoda mersului invers

Answer 2

3+3×[3+3×(3+3×3)]=(3×a+3)×3+3
3+3×[3+3×(3+9)]=(3×a+3)×3+3
3+3×(3+3×12)=(3×a+3)×3+3
3+3×(3+36)=(3×a+3)×3+3
3+3×39=(3×a+3)×3+3
3+117=(3×a+3)×3+3
120=(3×a+3)×3+3
120-3=(3×a+3)×3
117=3×a+3
117:3=3×a+3
39-3=3×a
36=3×a
a=36:3
a=12


Succes!!!