Question

a;b;c apartin numerelor naturale.
a+b+c=57
2a+b+2c=73

Calculati (a+c)x(5a+2b+5c)=

Answer 1

Daca a+b+c=57
Si 2a+b+2c=73
Inseamna ca 2a+2b+2c=57*2=114
Inlocuim
73+b=114
b=114-73
b=41<=>2b=82(1)
deci 2(a+c)=73-41
2(a+c)=32
a+c=16<=>5a+5c=80(2)

din (1) si (2)
=> (a+c)*(5a+2b+5c)=16*(80+82)=16*162=2560
Pwp (Sper ca nu am gresit la calcule) ... se mai intampla xd