Question

Aflati 3 numere naturale a,b,c stiind ca a+b=38 a+c=42 b+c=54

Answer 1

scazand primele doua ecuatii obtii -b+c=4;adunand noua ecuatie cu b+c=54=>2c=58=>c=29
a+c=42=>a=13
a+b=38=>b=25

Answer 2

[tex]a+b=38\\a+c=42\\b+c=54\\(a+b)+(a+c)+(b+c)=38+42+54\\2a+2b+2c=134\\2*(a+b+c)=134\\ a+b+c=\frac{134}{2}\\a+b+c=67\\a=(a+b+c)-(b+c)=67-54=13\\b=(a+b+c)-(a+c)=67-42=25\\ c=(a+b+c)-(a+b)=67-38=29\\Sfarsit![/tex]