\(\left(3\dfrac{1}{2}-x\right).1\dfrac{1}{4}=-1\dfrac{1}{20}\)
\(\left(\dfrac{7}{2}-x\right).\dfrac{5}{4}=-\dfrac{21}{20}\)
\(\dfrac{7}{2}-x=-\dfrac{21}{20}:\dfrac{5}{4}\)
\(\dfrac{7}{2}-x=-\dfrac{21}{25}\)
\(x=\dfrac{7}{2}-\left(-\dfrac{21}{25}\right)\)
\(x=\dfrac{217}{50}\)
Vậy \(x=\dfrac{217}{50}\)\(\)
\(\left(3\dfrac{1}{2}-x\right).1\dfrac{1}{4}=-1\dfrac{1}{20}\)
\(\left(\dfrac{7}{2}-x\right).\dfrac{5}{4}=-\dfrac{21}{20}\)
\(\left(\dfrac{7}{2}-x\right)=-\dfrac{21}{25}\)
\(x=\dfrac{217}{50}\)
\(\left(3\dfrac{1}{2}-x\right).1\dfrac{1}{4}=-1\dfrac{1}{20}\)
\(\left(\dfrac{7}{2}-x\right).\dfrac{5}{4}=\dfrac{-21}{20}\)
\(\left(\dfrac{7}{2}-x\right)=\dfrac{-21}{20}:\dfrac{5}{4}\)
\(\dfrac{7}{2}-x=\dfrac{-21}{20}.\dfrac{4}{5}\)
\(\dfrac{7}{2}-x=\dfrac{\left(-21\right).4}{20.5}\)
\(\dfrac{7}{2}-x=\dfrac{\left(-21\right).1}{5.5}\)
\(\dfrac{7}{2}-x=\dfrac{-21}{25}\)
\(x=\dfrac{7}{2}-\dfrac{-21}{25}\)
\(x=\dfrac{175}{50}+\dfrac{42}{50}\)
\(x=\dfrac{217}{50}\)
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