Áp dụng t/c dtsbn:
a) \(\dfrac{a}{4}=\dfrac{b}{7}=\dfrac{a-b}{4-7}=\dfrac{33}{-3}=-11\)
\(\Rightarrow\left\{{}\begin{matrix}a=\left(-11\right).4=-44\\b=\left(-11\right).7=-77\end{matrix}\right.\)
b) \(\dfrac{a}{11}=\dfrac{b}{15}=\dfrac{c}{22}=\dfrac{a+b-c}{11+15-22}=\dfrac{-8}{4}=-2\)
\(\Rightarrow\left\{{}\begin{matrix}a=\left(-2\right).11=-22\\b=\left(-2\right).15=-30\\c=\left(-2\right).22=-44\end{matrix}\right.\)
c) \(\dfrac{a}{4}=\dfrac{b}{3}=\dfrac{c}{6}=\dfrac{a-b+c}{4-3+6}=\dfrac{49}{7}=7\)
\(\Rightarrow\left\{{}\begin{matrix}a=7.4=28\\b=7.3=21\\c=7.6=42\end{matrix}\right.\)
a, Áp dụng t/c dtsbn:
\(\dfrac{a}{4}=\dfrac{b}{7}=\dfrac{a-b}{4-7}=\dfrac{33}{-3}=-11\\ \Rightarrow\left\{{}\begin{matrix}a=-44\\b=-77\end{matrix}\right.\)
b, Áp dụng t/c dtsbn:
\(\dfrac{a}{11}=\dfrac{b}{15}=\dfrac{c}{22}=\dfrac{a+b-c}{11+15-22}=\dfrac{-8}{4}=-2\\ \Rightarrow\left\{{}\begin{matrix}a=-22\\b=-30\\c=-44\end{matrix}\right.\)
c, Áp dụng t/c dtsbn:
\(\dfrac{a}{4}=\dfrac{b}{3}=\dfrac{c}{6}=\dfrac{a-b+c}{4-3+6}=\dfrac{49}{7}=7\\ \Rightarrow\left\{{}\begin{matrix}a=28\\b=21\\c=42\end{matrix}\right.\)
