2. Lesson Menu Main Idea Key Concept:Subtract Integers Example 1:Subtract Positive Integers Example 2:Subtract Positive Integers Example 3:Subtract Negative Integers Example 4:Subtract Negative Integers Example 5:Evaluate an Expression Example 6:Real-World Example

3. Main Idea/Vocabulary Use the rules for subtracting integers.

4. Key Concept

5. Example 1 Subtract Positive Integers Find 2 – 15. 2 – 15 = 2 + (–15) To subtract 15, add –15. = –13 Simplify. Answer: –13

6. Example 1 CYP A.–15 B.–7 C.7 D.15 Find 4 – 11.

7. Example 2 Find –13 – 8. Subtract Positive Integers –13 – 8 = –13 + (–8) To subtract 8, add –8. = –21 Simplify. Answer: –21

8. Example 2 CYP A.24 B.20 C.–20 D.–24 Find –22 – 2.

9. Example 3 Subtract Negative Integers Find 12 – (–6). 12 – (–6) = 12 + 6To subtract –6, add 6. = 18 Simplify. Answer: 18

10. Example 3 CYP A.–17 B.–9 C.9 D.17 Find 4 – (–13).

11. Example 4 Find –21 – (–8). Subtract Negative Integers –21 – (–8) = –21 + 8 To subtract –8, add 8. = –13 Simplify. Answer: –13

12. Example 4 CYP A.9 B.7 C.–7 D.–9 Find –8 – (–1).

13. Example 5 Evaluate an Expression ALGEBRA Evaluate g – h if g = –2 and h = –7. g – h = –2 – (–7) Replace g with –2 and h with –7. = –2 + (7)To subtract –7, add 7. = 5Simplify. Answer: 5

14. Example 5 CYP A.10 B.8 C.–8 D.–10 ALGEBRA Evaluate f – x if f = –1 and x = –9.

15. Example 6 GEOGRAPHY In Mongolia, the temperature can fall to –45°C in January. The temperature in July may reach 40°C. Find the difference between these two temperatures in Mongolia. Subtract the lower temperature from the higher temperature. 40 – (–45)= 40 + 45To subtract –45, add 45. = 85Simplify. Answer: The difference between the temperatures is 85°C.

16. Example 6 CYP A.–101°C B.–81°C C.81°C D.101°C TEMPERATURE The temperature in Michigan fell to a low of –10°C in January, while in California the temperature reached a high of 91°C. Find the difference between the temperatures in these two states.