\(\frac{b}{3}\Rightarrow\frac{2b}{6};\frac{c}{4}\Rightarrow\frac{3c}{12}\)
\(\frac{a}{2}=\frac{2b}{6}=\frac{3c}{12}\)
Áp dụng dãy tỉ số bằng nhau ta có:
\(\frac{a}{2}=\frac{2b}{6}=\frac{3c}{12}=\frac{a+2b-3c}{2+6-12}=\frac{-20}{-4}=5\)
\(\frac{a}{2}=5\Rightarrow a=10\)
\(\frac{2b}{6}=5\Rightarrow b=15\)
\(\frac{3c}{12}=5\Rightarrow c=20\)
tíc mình nha