Worked examples
Two examples
Example 1
4 − 9 =
- Subtract a positive. Rewrite: 4 + (−9).
- Different signs. First subtract: 9 − 4 = 5. The original larger absolute value is −9, so the answer is negative.
Answer: −5
Example 2
−5 − 6 =
- Subtract a positive. Rewrite: −5 + (−6).
- Same signs: 5 + 6 = 11, and keep the negative sign.
Answer: −11
Where this is taught: Signed Numbers, Part 8: every kind of subtraction
The drill
Ten problems
How many:
Type each answer, then press Check my answers at the bottom. For a minus sign, the hyphen key (-) is fine.Write each answer on the line. The answer key, with the reasoning, is on the last page.