Question

Determinati numerele prime a,b,c stiind ca 2a+4b+9c=34

Answer 1

2a+4b+9c=34
9c=2(17-a-2b) => 9c e divizibil cu 2, deci c e par
c prim si c par => c=2
2a+4b+9·2=34
2(a+2b)=34-18=16  |:2
a+2b=8 => a e par, deci a=2
2b=8-2
b=6:2
b=3
R: a=2; b=2; c=3
verificare:
2·2+4·3+9·2=34
4+12+18=34 (A)