a+2b+4c=58
48 par, 2b , par,4c par,deci a este par
dar a este prim deci a=2
2+2b+4c=58 |:2
1+b+2c=29
b+2c=28
2c par, 28 par.deci b par
deci b=2
2c=26
c=13 prim , adevarat
(a;b;c)∈{(2;2;13)}
verificare 2*1+2*2+4*13=2+4+52=6+52=58
adevarat , bine rezolvat
as simple as that!