Mathematical+Reflections+4

D.D 7E 1/05/10

Mathematical Reflection 4

Big Idea: Negative numbers help us model real world situations. Essential Question: How do I multiply and divide integers? Class Notes:
 * if one number is negative, the answer will be negative
 * if both numbers are negative, the answer will be positive
 * rules for multiplying apply for dividing

Questions 1 and 2

1.**Write a strategy for multiplying two integers. Be sure to consider all possible combinations of positive integers, negative integers, and 0. Verify your strategy by finding the following products.** Some strategies for multiplying two integers are: A positive multiplied by a positive is a positive. A negative multiplied by a negative is a positive. A negative multiplied by a positive (or the other way around) is a negative. Anything multiplied by 0 is 0.

A. -13x7 = -101 B. 11x-20 =-220 C. -12x0 =0 D. -18x-22 =506

2. **Write a strategy for dividing two integers. Be sure to consider all possible combinations of positive integers, negative integers, and 0. Verify your strategy by finding the following quotients.** Some strategies for dividing to integers are: A positive divided by a positive is a positive. A negative divided by a negative is a positive. A negative divided by a positive (or the other way around) is a negative. 0 divided by anything is impossible.

A. 126 divided by -9 =-14 B. -36 divided by -12 =3 C. -2592 divided by 32 =-81 D. 0 divided by 18 =0

Summary

In this unit we learned how to multiply and divide negative and positive integers. We also learned how to find patterns in multiplying and dividing.