\(7x=3y\Rightarrow\dfrac{x}{3}=\dfrac{y}{7}=\dfrac{x-y}{3-7}=\dfrac{6}{-4}=-\dfrac{3}{2}\)
\(\Rightarrow\left\{{}\begin{matrix}\dfrac{x}{3}=\dfrac{-3}{2}\\\dfrac{y}{7}=\dfrac{-3}{2}\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}2x=-3.3\\2y=-3.7\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\dfrac{-9}{2}\\y=\dfrac{-21}{2}\end{matrix}\right.\)
\(Vậy\)\(x=\dfrac{-9}{2}và,y=\dfrac{-21}{2}\)
7x=3y⇒x3=y7=x−y3−7=6−4=−327x=3y⇒x3=y7=x−y3−7=6−4=−32
⇒⎧⎪ ⎪⎨⎪ ⎪⎩x3=−32y7=−32⇒[2x=−3.32y=−3.7⇒⎡⎢ ⎢⎣x=−92y=−212⇒{x3=−32y7=−32⇒[2x=−3.32y=−3.7⇒[x=−92y=−212
VậyVậyx=−92và,y=−212
(có đáp án)
