Worked examples
Two examples
Example 1
4 + (−9) =
- Different signs, Rule 2. Two steps.
- First subtract: 9 − 4 = 5.
- Then give the result the sign of the original larger absolute value. That is −9, which is negative.
Answer: −5
Example 2
−20 + 7 =
- Different signs, Rule 2.
- First subtract: 20 − 7 = 13.
- The original larger absolute value is −20, which is negative.
Answer: −13
Where this is taught: Signed Numbers, Part 6: Rule 2
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.