Question

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\(\dfrac{-21}{10}+\dfrac{21}{10}.\dfrac{3}{4}-\dfrac{3}{4}\)

Answer 1

\(\dfrac{-21}{10}+\dfrac{21}{10}.\dfrac{3}{4}-\dfrac{3}{4}=\dfrac{21}{10}\left(-1+\dfrac{3}{4}\right)-\dfrac{3}{4}=\dfrac{21}{10}.\dfrac{-1}{4}-\dfrac{3}{4}=\dfrac{-21}{40}-\dfrac{3}{4}=\dfrac{-21}{40}-\dfrac{30}{40}=\dfrac{-51}{40}\)

Answer 2

\(\dfrac{-21}{10}+\dfrac{21}{10}.\dfrac{3}{4}-\dfrac{3}{4}\)=\(\left\{\dfrac{-21}{10}+\dfrac{21}{10}\right\}.\left\{\dfrac{3}{4}-\dfrac{3}{4}\right\}\)= \(0.0\) =0