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
• Use the rules for subtracting integers.
Subtract Positive Integers

Find 2 – 15.

2 – 15 = 2 + (–15) To subtract 15, add –15.

      = –13        Simplify.



Answer: –13
Find 4 – 11.

A. –15


B. –7


C. 7


D. 15
Subtract Positive Integers

Find –13 – 8.

–13 – 8 = –13 + (–8)      To subtract 8, add –8.

        = –21             Simplify.



Answer: –21
Find –22 – 2.

A. 24


B. 20


C. –20


D. –24
Subtract Negative Integers

Find 12 – (–6).

12 – (–6) = 12 + 6         To subtract –6, add 6.

          = 18             Simplify.



Answer: 18
Find 4 – (–13).

A. –17


B. –9


C. 9


D. 17
Subtract Negative Integers

Find –21 – (–8).

–21 – (–8) = –21 + 8        To subtract –8, add 8.

           = –13            Simplify.



Answer: –13
Find –8 – (–1).

A. 9


B. 7


C. –7


D. –9
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.

     =5              Simplify.



Answer: 5
ALGEBRA Evaluate f – x if f = –1 and x = –9.

A. 10


B. 8


C. –8


D. –10
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 + 45      To subtract –45, add 45.

          = 85            Simplify.

Answer: The difference between the temperatures
        is 85°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.
A. –101°C

B. –81°C

C. 81°C

D. 101°C
Subtract integers

Subtract integers

  • 2.
    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.
    • Use therules for subtracting integers.
  • 5.
    Subtract Positive Integers Find2 – 15. 2 – 15 = 2 + (–15) To subtract 15, add –15. = –13 Simplify. Answer: –13
  • 6.
    Find 4 –11. A. –15 B. –7 C. 7 D. 15
  • 7.
    Subtract Positive Integers Find–13 – 8. –13 – 8 = –13 + (–8) To subtract 8, add –8. = –21 Simplify. Answer: –21
  • 8.
    Find –22 –2. A. 24 B. 20 C. –20 D. –24
  • 9.
    Subtract Negative Integers Find12 – (–6). 12 – (–6) = 12 + 6 To subtract –6, add 6. = 18 Simplify. Answer: 18
  • 10.
    Find 4 –(–13). A. –17 B. –9 C. 9 D. 17
  • 11.
    Subtract Negative Integers Find–21 – (–8). –21 – (–8) = –21 + 8 To subtract –8, add 8. = –13 Simplify. Answer: –13
  • 12.
    Find –8 –(–1). A. 9 B. 7 C. –7 D. –9
  • 13.
    Evaluate an Expression ALGEBRAEvaluate 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. =5 Simplify. Answer: 5
  • 14.
    ALGEBRA Evaluate f– x if f = –1 and x = –9. A. 10 B. 8 C. –8 D. –10
  • 15.
    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 + 45 To subtract –45, add 45. = 85 Simplify. Answer: The difference between the temperatures is 85°C.
  • 16.
    TEMPERATURE The temperaturein 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. A. –101°C B. –81°C C. 81°C D. 101°C