Question

2x = 5y và y - 3x = -78

Answer 1

\(2x=5y\Rightarrow\dfrac{x}{5}=\dfrac{y}{2}\)

Áp dụng t/c dtsbn:

\(\dfrac{x}{5}=\dfrac{y}{2}=\dfrac{3x}{15}=\dfrac{y-3x}{2-15}=\dfrac{-78}{-13}=6\)

\(\Rightarrow\left\{{}\begin{matrix}x=6.5=30\\y=6.2=12\end{matrix}\right.\)

Answer 2

\(2x=5y\Rightarrow\dfrac{x}{5}=\dfrac{y}{2}\)

Áp dụng t/c dtsbn:

\(\dfrac{x}{5}=\dfrac{y}{2}=\dfrac{3x}{15}=\dfrac{y-3x}{2-15}=\dfrac{-78}{-13}=6\\ \Rightarrow\left\{{}\begin{matrix}x=30\\y=12\end{matrix}\right.\)

Answer 3

Rất gấp đó, các bạn trả lời giúp mình nha!!!