Solve for Missing Divisor in -9×-7÷?=-3: Step-by-Step Solution

$-9\cdot-7:?=-3$

Let's write the exercise in the following way:

$\frac{-9\times-7}{?}=-3$

Note that in the numerator we are multiplying between two negative numbers, therefore the result must be a positive number:

$\frac{9\times7}{?}=-3$

Let's multiply by the question mark and get:

$9\times7=-3\times\text{?}$

Let's divide by negative 3 and get:

$\frac{9\times7}{-3}=\text{?}$

Let's factor the 9 into a multiplication exercise:

$\frac{3\times3\times7}{-3}=\text{?}$

Let's reduce between the 3 in the numerator and denominator, noting that we are dividing a positive number by a negative number, therefore the result must be a negative number:

$-3\times7=\text{?}$

$-21=\text{?}$