23
Adding and Subtracting Negative Numbers
To add a negative number, move to the left on the number line. To subtract a negative number,
move to the right on the number line.
1. 5 – 7 =
2. 3 + 4 – 1 =
3. –8 + –3 =
4. 4 – (–7) + 3 =
5. 347 + 15 – 187 =
6. –38 + 19 – (–205) =
7. 1,108 – 386 + (–117) =
8. 94 – 18 + (–52) + 42 =
9. –61 + 39 + 9 – (–3) =
10. 2,039 – 761 – 78 + 15 =
Skills Workshop 7
When subtracting negative numbers, the negative sign is cancelled by the operation. Subtracting a
negative number is the same as adding a positive number of the same value: 2 – (–5) = 2 + 5 = 7. Identify
the sign of each number, compare the sign to the operation, and determine which direction to move on
the number line.
See It
Solve the equation: 10 – 5 – (–2) =
Step 1: The integers 10 and 5 are positive, but the integer 2 is negative.
Step 2: Positive 5 is subtracted from 10. Negative 2 is subtracted from the previous
result, so change the operation to addition and remove the negative sign.
Step 3: Starting at 10 on the number line, move 5 places to the left to end at 5.
Step 4: Starting at 5 on the number line, move 2 places to the right to end at the
answer of 7.
Check It
0 5
Subtracting Negative Numbers
10 15 20
Adding Negative Numbers
5
+2
7
–5
10
5 10 0