Pre-Algebra · Integers and negative numbers

How to Divide Negative Numbers

Problem

−42÷7-42 \div 7

Answer

−6-6

Division works like multiplication for signs: two negatives make a positive, and one negative makes a negative. Divide first, then fix the sign.

Step-by-step solution

  1. Divide the numbers and ignore the signs for now.

    42÷7=642 \div 7 = 6

    Why: The size of the quotient comes from the two numbers.

  2. Count the negative signs.

    1 negative sign1\ \text{negative sign}

    Why: Only the dividend is negative.

  3. Apply the sign rule.

    odd count⇒negative quotient\text{odd count} \Rightarrow \text{negative quotient}

    Why: Division follows the same sign rules as multiplication.

  4. Write the answer with the sign.

    −6-6

    Why: One negative number, so the quotient is negative.

Common mistakes

  • Making the answer positive because 42 is larger than 7. The sign count decides.
  • Dividing in the wrong order and using 7 divided by 42.
  • Copying the rule for addition. The sign rules for division are not the same as the rules for adding.

Practice problems

Use the same method. Work each problem on paper, then open the answer to check.

  1. −25÷5-25 \div 5

    Show answer

    −5-5

  2. −48÷(−6)-48 \div (-6)

    Show answer

    88

  3. 72÷(−9)72 \div (-9)

    Show answer

    −8-8

  4. −81÷(−9)-81 \div (-9)

    Show answer

    99

  5. −18÷3-18 \div 3

    Show answer

    −6-6