Mathematical+Reflections,+p+66+0910

B.L.   Math 7D 05/01   Big Idea - Negative numbers help us to model many real world situations Essential Question #4 - How do I multiply and divide integers? Mathematical Reflections 4 (ATN) *Notes from class - Multiplying and dividing integers (--) = +, (++) = +, (-+) = -, (+-) = -. Dividing/Multiplying odd amount of negative integers = negative answer. Dividing/Multiplying even amount of negative integers = positive answer. *Vocabulary - Integer = A whole number, negative or positive 1. If the combination includes 0, the product would be 0. If the combination includes positive and/or negative integers, you can follow this simple rule. If the amount of negative integers are even, the product would be a positive number ((--) = +). If the amount of negative integers are odd, the product would be a negative number ((+-), (-+) = -). This rule applies to a combination of more than 2 numbers. 1a. -13*7 (1 negative integer (odd) = negative product) = -91 1b. 11*-20 (1 negative integer (odd) = negative product) = -220 1c. -12*0 (0 is included = product is 0) = 0 1d. -18*-22 (2 negative integers (even) = positive product) = 396 2. If the combination includes 0, the quotient would be called unidentified. If the combination includes positive and/or negative integers, you can follow this similar rule to the one for multiplication. If the amount of negative integers are even, the quotient would be a positive number ((--) = +). If the amount of negative integers are odd, the quotient is a negative number ((+-) = -, (-+) = -). This rule also applies to a combination of more than 2 numbers. a. 126/-9 (1 negative integer (odd) = negative quotient) = -14 b. -36/-12 (2 negative integers (even) = positive quotient) = 3 c. -2592/32 (1 negative integer (odd) = negative quotient) = -81 d. 0/18 (0 is included = quotient is 0) = 0 Summary - I have learned a very simple rule that applies to both multiplying and dividing combinations of both positive and negative integers. Somehow similar to the universal rule of zero, this rule applies to a combination of more than two numbers. If the number sentence includes a zero, the answer is zero. If the number sentence includes negative integers, count the amount of negative integers. If it is odd, the answer is negative. If it is even, the answer is positive.