1. Illustrate the following sums using a (i) vector model, (ii) 5. Create word problems as described: money model, (iii) chip model: a) -13 + 32 using the vector model, a ) 7+ (-3 ) b) 343 + (-44) using the money model, b) - 8+ (-9). c) -78 + (-22) using the vector model, 2. (Mental Math) Compute the following mentally and write d) -35 + (-189) using the money model. down your answer in a way that shows your thinking: a) -984 + (537 + 984) 6. a) Find the absolute values: |0|, [13 - 8), and b) 136 + (-97) + (-76). 18 - 13. 3. Are the following statements true or false? Give an exam- b) For which numbers a is -a positive? For which is ple to illustrate your answer. - la positive? c) A student claims that la| = -a is true only for a) Every integer is a whole number. a = 0. Explain why the student is wrong. What b) The sum of two negative numbers is always negative. misconception does the student have about -a? c) A negative number plus a positive number is always 7. The most important facts about the absolute value are that negative. la| 2 0 for any number a, and la| = 0 only when a = 0. d) A positive number plus a negative number is always Why are these facts clear from the definition? negative. e) To add two negative numbers, we find the sum of 8. Use the vector model to verify the following identities. their absolute values and take the negative sign for a) a+(-a) = 0 (draw one picture for a > 0, another the answer. for a 0, b > 0, another for a > 0, b