2. Integers Get It! Got It! GREAT! What is an Integer? Integers are all the whole numbers greater than zero: 1, 2, 3, 4, 5… and their opposite numbers less than zero: -1,-2,-3,-4,-5… Integer is 17 Opposite is -17 Integer is -8 Opposite is 8 Integer is 23 Opposite is -23
3. Integers Integers on a Number Line Negative Integers are opposite whole numbers less than zero: -1,-2,-3,-4,-5… Positive Integers are whole numbers greater than zero: 1,2,3,4, 5… 0 …-5,-4,-3,-2,-1 1,2,3,4,5...
4. Integers How to add positive & positive integers Positive Integers are whole numbers greater than zero: 1,2,3,4, 5… 3 5 +
5. Integers They are BOTH positive Therefore… add numbers And KEEP IT POSITIVE! 3 5 + 1 2 4 3 5 6 7 8
8. Integers Notice how positive and negatives are opposites going two different directions 1 -1
9. Integers Notice how positive and negative touch ends or points but don’t point in the same direction. 0 0 …-5,-4,-3,-2,-1 0 1,2,3,4,5...
10. Integers Positive 1/negative-1cancel out to zero. 1 0 0 As per number line -1 Positive 1/positive 1& negative -1/negative -1 follow the same direction and increase 2 or decrease -2. 1+1= 2 -1+ -1= -2
12. Integers -3 5 + 5-3=2 5 is bigger and positive so answer must be positive. 1 2 0 0 0 Hint: Subtract both numbers and keep the sign of the bigger whole number.
13. Integers Subtracting Integers Adding and subtracting integers is almost identical. We convert the subtraction symbol to addition and give the following number its opposite sign. -2 - 3 -2 + -3 = -5 Change – to + and opposite of 2 is -2 5 - 7 5 + -7 = -2 -2 – -8 -2 + 8 = 6 Change – to + and opposite of 7 is -7 Change – to + and opposite of -8 is 8