Question

Tìm a; b ; c biết \(\frac{3a-2b}{5}=\frac{2c-5a}{3}=\frac{5b-3c}{3}vàa+b+c=-50\)

Answer 1

\(\frac{2c-5a}{3}=\frac{5b-3c}{3}\Rightarrow2c-5a=5b-3c\Rightarrow a+b=c\)

Mà \(a+b+c=-50\Rightarrow2c=-50\Rightarrow c=-25\); \(a+b=-25\)

\(\frac{3a-2b}{5}=\frac{2c-5a}{3}\Rightarrow9a-6b=-250-25a\Rightarrow34a-6b=-250\)

\(\Rightarrow40a-6\left(a+b\right)=-250\Rightarrow40a=-250+6.\left(-25\right)=-400\)

\(a=-10\);      => \(b=-25-a=-25+10=-15\)

Vậy a= -10 ; b = -15  ; c= -25