Adding integers

Today’s Objective IWBAT add integers.

Example: -3, -2, -1, 0, 1, 2, 3 Definition Integer – any positive or negative number, excluding fractions, decimals, or percents. Example: -3, -2, -1, 0, 1, 2, 3

But I don’t know how to add integers!!! I think that I am going to … FREAK OUT!!!

No vorries children! Adding integers is not that different from adding whole numbers.

How do I Add Integers? There are 3 ways that I use to add integers: 1.) Number Line 2.) Counters 3.) Song

How do I Add Integers? The Number Line Method To use the number line, follow these steps: 1.) Start at the point of the first number 2.) Then do one of two things: a) If the second number is positive, go to the right the number of spaces b) If the second number is negative, go to the left the number of spaces

How do I Add Integers? The Number Line Method Simplify: -3 + 7 Move the point 7 spaces to the RIGHT 4 -3 -5 -4 -3 -2 -1 1 2 3 4 5 6 7 8 9

How do I Add Integers? The Number Line Method Simplify: 4 + (-5) Move the point 5 spaces to the LEFT 4 -1 -5 -4 -3 -2 -1 1 2 3 4 5 6 7 8 9

How do I Add Integers? The Number Line Method Simplify: -5 + 2 Move the point 2 spaces to the RIGHT -5 -3 -5 -4 -3 -2 -1 1 2 3 4 5 6 7 8 9

How do I Add Integers? The Counters Method To use the counters method, follow these steps: 1.) Make a T-Chart 2.) Use “+” signs to represent the positive number and “-” to represent the negative number 3.) Cross out every “+” that you have a “-” for 4.) Count what you have left. That is your answer. If you have more “+” left, your answer is positive; if you have more “-” left, your answer is negative.

How do I Add Integers? The Counters Method Simplify 9 + (-5) 9 -5 - - + + + + - - + + - + + +

How do I Add Integers? The Counters Method Simplify -8 + 3 -8 3 + + - - - - + - - - -

How do I Add Integers? The Counters Method Simplify -3 + 7 -3 7 + + - - - + + + + +

The number line and counters methods only work with small numbers!! So if you have bigger numbers (which you will), you need to use the next method: The Song A word of warning!!!! The number line and counters methods only work with small numbers!!

How do I Add Integers? The Song Method To add integers, simply sing this song to the tune of Row, Row, Row, Your Boat: Same signs add and keep Different signs subtract Take the sign of the higher # Then you’ll be exact!!

How do I Add Integers? The Song Method Simplify -32 + 41 same or different add or subtract positive or negative

How do I Add Integers? The Song Method Simplify -21 + 14 same or different add or subtract positive or negative

How do I Add Integers? The Song Method Simplify -15 + (-20) same or different add or subtract positive or negative

EXIT TICKET 1. (–2) + (–9) + 18 2. (–25) + 5 + –11 3. 14 + –3 + –8