Worked examples
Two examples
Example 1
−3 + (−5) =
- Adding, not multiplying. Same signs, Rule 1: 3 + 5 = 8, keep the negative.
Answer: −8
Example 2
(−3) × (−5) =
- Multiplying. Same signs: positive. 3 × 5 = 15.
Answer: 15
Where this is taught: Signed Numbers, Part 10: do not mix up the two sets of rules
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.