2.2+Inventing+a+New+Model+0910

17.04.10 A.B

**Big Idea**
 * Negative numbers help us to model many real world situations. **
 * Essential Question: ** How can I add integers?


 * Notes from class:**
 * An absolute value is the number’s distance from the zero
 * If the absolute value of a number is bigger than the answer will always get that number’s symbol.


 * Problem 2.2: __Inventing A New Model__**


 * A. Use a chip board and black and red chips to find each sum. Draw each series of chip boards to illustrate your work.**
 * 1) -8+-7=-1
 * 2) -8+7=-15
 * 3) 8+-7=1
 * 4) 8+7=15


 * B. Find two combinations of black and red chips that will simplify to represent the given integer. Draw a series of chip boards to prove that each combination works.**
 * -3
 * +5


 * C.** **Write each combination you found in part B as an addition sentence.**
 * 1) -2+-1=-3
 * 2) 3+2=5


 * Problem 2.2 follow-up:**

-8+4=-4
 * 1. What integer added to -8 gives a sum of -4?**

-2+-4=-6
 * 2. Give two integers with a sum that is less than either of the two integers.**

5+7=12
 * 3. Give two integers with a sum that is greater than wither of the two integers.**

a. 9+-7=2 b. -80+50=30 c. 35+-27=8 d. -8+-5=-13
 * 4. Use Conrado’s method to compute the following sums in your head.**