\(\dfrac{14}{-21}+\dfrac{18}{36}=\dfrac{-2}{3}+\dfrac{1}{2}=\dfrac{-4}{6}+\dfrac{3}{6}=\dfrac{-1}{6}\)Vì \(\dfrac{-1}{6}=\dfrac{-1}{6}\Rightarrow\dfrac{14}{-21}+\dfrac{18}{36}=\dfrac{-1}{6}\)Câu trả lời: \(\dfrac{14}{-21}+\dfrac{18}{36}=\dfrac{-2}{3}+\dfrac{1}{2}=\dfrac{-4}{6}+\dfrac{3}{6}=\dfrac{-1}{6}\)Vì \(\dfrac{-1}{6}=\dfrac{-1}{6}\Rightarrow\dfrac{14}{-21}+\dfrac{18}{36}=\dfrac{-1}{6}\)