Question

Daca a,b,c sunt numere naturale astfel incât a+b+c=57 si 2a+b+2c=73,calculati (a+c)×(5×a+2×b +5×c)

Answer 1

73=2a+b+2c=(a+b+c)+(a+c)=57+(a+c), deci
a+c=16

5a+2b+5c=2(2a+b+2c)+(a+c)=2*73+16=162 deci rezultatul cerut este:

16*162=2592