Find the equations −8.58÷◻=3.9 −3.2×◻=24

c) A division fact of $a÷b=c$ is equivalent to the division fact $a÷c=b$.

Therefore $-8.58÷◻=3.9$ is equivalent to the division fact $-8.58÷3.9=\square ◻$.

Since $-8.58÷3.9=-2.2$, then $-8.58÷-2.2=3.9.$
d) A multiplication fact of $a\times b=ca\times b=c$ is equivalent to the division fact $b=c÷a$.

Therefore $-3.2\times ◻=24$ is equivalent to the division fact $◻=24÷(-3.2)◻$.

Since $24÷(-3.2)=-7.524÷(-3.2)=-7.5$, then $-3.2\times -7.5=24.$