Adding and Adding and SubtractingSubtracting

IntegersIntegers

Adding and Adding and SubtractingSubtracting

IntegersIntegers

1.Graph the following set of Integers…

{ 3, 0, -2 }<---|---|---|---|---|---|---|---|---|--->

-3 -2 -1 0 1 2 3 4 5

2. Name the set of integers graphed.

<---|---|---|---|---|---|---|---|---|---> -3 -2 -1 0 1 2 3 4 5

{ -3, -1, 2, 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) FIRST FIX YOUR

DOUBLE SIGNS 20 – 5 WHAT’S THE RULE? DO I ADD OR SUBTRACT? 15

4. (-2) + (-17) FIRST

FIX YOURDOUBLE SIGNS

-2 – 17 READ THIS AS NEGATIVE 2 AND NEGATIVE 17

WHAT’S THE RULE? DO I ADD OR SUBTRACT? -19

5. (-7) + 5 + (-2) FIRST

FIX YOURDOUBLE SIGNS

-7 + 5 - 2 READ THIS AS NEGATIVE 7 AND POSITIVE 5

WHAT’S THE RULE? DO I ADD OR SUBTRACT?- 2 - 2

READ THIS AS NEGATIVE 2 AND NEGATIVE 2

WHAT’S THE RULE? DO I ADD OR SUBTRACT?

- 4

Subtracting IntegersWhat’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)

FIRST FIX YOUR

DOUBLE SIGNS

-9 + 11 READ THIS AS NEGATIVE 9 AND POSITIVE 11

WHAT’S THE RULE? DO I ADD OR SUBTRACT?2

7. 6 – 11 READ THIS AS POSITIVE 6 AND NEGATIVE 11

WHAT’S THE RULE? DO I ADD OR SUBTRACT?-5

NO DOUBLE SIGNS THIS TIME

8. -34 – 20

READ THIS AS NEGATIVE 34 AND NEGATIVE 20

WHAT’S THE RULE? DO I ADD OR SUBTRACT?-54

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 -13

-1 -13

-14

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

REMEMBER FIX YOUR

DOUBLE SIGNS

15,586 + 239

15,825

b) A city is at 6,886 feet above sea level. Is this closer to the highest point or the lowest point?

15,586

- 6,886

6,886

- -239

8,700 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

REMEMBER FIX YOUR

DOUBLE SIGNS

15,802 + 227

16,029

b) A city is at 9,161 feet above sea level. Is this closer to the highest point or the lowest point?

15,802

- 9,161

9,161

- -227

6,641 9,388