Rules
Which way do you move when you add a positive number?
Right
Add the integers
6+(-4)
2
Subtract the integers
7 - 10
What is -3?
-6+(-6) = 12
False, -12
When Steve woke up. His temperature was 102 F. Two hours later it was 3 lower. What was his temperature then?
99 F
Which way do you move when you add a negative number?
Left
Add the integers
-3+2
-1
Subtract the integers
-5 - 7
What is -12?
-8-(-6)= -14
False -2
An elevator is on the twentieth floor. It goes down 11 floors and then up 5 floors. What floor is the elevator on now?
10
What is the rule when you subtract a negative number?
Change it to positive or adding.
Add the integers
-5+ (-6)
-11
Subtract the integers
6- (-4)
What is 10?
9+(-7) = 2
True
A deep-sea exploring ship is pulling up a diver at the rate of 25 feet per minute. The diver is 200 feet below sea level. How deep was the diver 10 minutes ago?
9
When adding integers with the same signs, there are two things you must do as a rule. What are they?
Add the integers and keep the sign.
Add the integers
-20 + 3
-17
Subtract the integers
-9 - (-4)
-5
-9-(-3)= -6
True
The average temperature at the South Pole is – 45 F. The average temperature on the Equator is 92 F. How much warmer is the average temperature on the Equator than at the South Pole?
-49
If you subtract a negative number FROM a negative number, is the answer always positive?
No, it depends on how large the negative number is.
Add the integers
-12 + (-4) + (-3)
-19
Subtract the integers
(-6) - 2 + 6
What is -2
-11-14= 3
False, -25
Two golfers completed one round of golf. The first golfer had a score of +6 and the second golfer had a score of –3. How many more shots did the first golfer take?
-56