\(\dfrac{\left(-9\right)\times14}{21\times\left(-45\right)}\)
\(=\dfrac{-126}{-945}=\dfrac{2}{15}\)
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\(\dfrac{\left(-12\right)\times14}{\left(-42\right)\times\left(-6\right)}\)
\(=\dfrac{-168}{252}=\dfrac{-2}{3}\)
\(\left(-9\right)\times\dfrac{14}{21}\times\left(-45\right)=\left(-9\right)\times\dfrac{2}{3}\times\left(-45\right)=\dfrac{-9}{1}\times\dfrac{2}{3}\times\left(-45\right)=\dfrac{-18}{3}\times\dfrac{-45}{1}=\dfrac{810}{3}=270\)
\(\left(-12\right)\times\dfrac{14}{-42}\times\left(-6\right)=\dfrac{-12}{1}\times\dfrac{-1}{3}\times\left(-6\right)=\dfrac{12}{3}\times\left(-6\right)=4\times\left(-6\right)=-24\)
