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

Question

97:?=3 -9\cdot-7:?=-3

Video Solution

Solution Steps

00:06 First, let's find the unknown value.
00:10 Next, write the division as a fraction. This makes it easier to work with.
00:22 Remember, a negative number times another negative always equals a positive.
00:36 Now, let's isolate the unknown variable by getting it alone on one side.
00:59 We can factor nine into three times three to help us simplify.
01:05 Let's reduce or simplify any terms we can.
01:11 Remember, positive divided by negative always equals negative.
01:20 And there you have it! This is the solution to our problem.

Step-by-Step Solution

Let's write the exercise in the following way:

9×7?=3 \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:

9×7?=3 \frac{9\times7}{?}=-3

Let's multiply by the question mark and get:

9×7=3×? 9\times7=-3\times\text{?}

Let's divide by negative 3 and get:

9×73=? \frac{9\times7}{-3}=\text{?}

Let's factor the 9 into a multiplication exercise:

3×3×73=? \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:

3×7=? -3\times7=\text{?}

21=? -21=\text{?}

Answer

21 -21