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Adding and Subtracting
Integers
1.Graph the following set of Integers…
{ 3, 0, -2 }
<---|---|---|---|---|---|---|---|---|--->
-3 -2 -1
0
1
2
3
5
4
2. Name the set of integers graphed.
<---|---|---|---|---|---|---|---|---|--->
-3 -2 -1
0
1
2
3
4
{ -3, -1, 2, 5 }
5
State the rule for adding integers
If the signs in front of the numbers are the
same, add the numbers and keep the signs.
If the signs in front of the numbers are
different, subtract the numbers and keep the
sign of the larger number.

3. 20 + (-5)
20 – 5
15
FIRST
FIX YOUR
DOUBLE SIGNS
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
4. (-2) + (-17)
FIRST
FIX YOUR
DOUBLE SIGNS
-2 – 17
READ THIS AS NEGATIVE 2 AND NEGATIVE 17
-19
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
5. (-7) + 5 + (-2)
-7 + 5 - 2
- 2
- 2
- 4
FIRST
FIX YOUR
DOUBLE SIGNS
READ THIS AS NEGATIVE 7 AND POSITIVE 5
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
READ THIS AS NEGATIVE 2 AND NEGATIVE 2
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
Subtracting Integers
What’s the rule????
Change the subtraction sign to a plus
sign, then change the sign of the
number after it.
Remember this? Keep-Change-Change
OR you can just “fix” your double signs and
follow the adding rules!!!!
6. -9 – (-11)
-9 + 11
2
FIRST
FIX YOUR
DOUBLE SIGNS
READ THIS AS NEGATIVE 9 AND POSITIVE 11
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
NO DOUBLE SIGNS
THIS TIME
7. 6 – 11
-5
READ THIS AS POSITIVE 6 AND NEGATIVE 11
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
8. -34 – 20
-54
READ THIS AS NEGATIVE 34 AND NEGATIVE 20
WHAT’S THE RULE? DO I ADD OR SUBTRACT?
9. The temperature in Cleveland, Ohio was -20 C
at 6 am. By noon that day the temperature had
risen 19 C. By 6pm, the temperature had fallen
13 C. What was the temperature at 6pm?
-20 +19
-1
-13
-14
-13
10. Nicole has $151 in her checking account.
She writes a check for $117, makes a deposit
of $49, then writes a check for $81. find the
amount left in her account.
+ 151 - 117 + 49 - 81
34
+ 49 - 81
83 - 81
2
11. The highest location in a certain foreign
country is 15,586 feet above sea level. The
lowest point in the same country is
239 feet below sea level.
a) Find the difference
in the two elevations.
+ 15,586
- 239
15,586 + 239
15,825
REMEMBER
FIX YOUR
DOUBLE SIGNS
b) A city is at 6,886 feet above
sea level. Is this closer to the
highest point or the lowest point?
6,886
15,586
-
6,886
8,700
-
-239
7,125
12. The highest location in a certain foreign
country is 15,802 feet above sea level. The
lowest point in the same country is
227 feet below sea level.
a) Find the difference
in the two elevations.
+ 15,802
- 227
15,802 + 227
16,029
REMEMBER
FIX YOUR
DOUBLE SIGNS
b) A city is at 9,161 feet above
sea level. Is this closer to the
highest point or the lowest point?
9,161
15,802
-
9,161
6,641
-
-227
9,388