What is -21/10 divided by 56/ 24. please explain how you did it.
\(\text{the key is that } \dfrac a b \div \dfrac c d = \dfrac a b \times \dfrac d c\\ -\dfrac{21}{10}\div \dfrac{56}{24} = -\dfrac{21}{10}\times \dfrac{24}{56} = -\dfrac{9}{10}\)