Kathleen's Integer Scribepost

8.2 Page 296 Questions 1, 3, 5 and 7

1.) Darcy modeled (+7) x (+3)  on a number line by drawing seven arrows. Ishnan modeled (+7) x (+3) on a number line by drawing only three arrows. Explain Ishnan's thinking.

Darcy did 7 groups of 3 while Ishnan did 3 groups of 7. It still works because the product is the same and Ishnan just "switched" the two numbers. 

3.) Without doing any calculations, Wei said that -19 and +27 have the same product as +19 and -27. How did she know?

5.) What multiplication statement does each diagram represent? 

a.) 2 x (-6) = -12

2 groups of negative 6 equals negative 12

b.) 4 x 4 = 16

4 groups of  4 equals 16

7.) Determine each product.

a.) (+4) x (-7) = -28

4 groups of -7

b.) (+2) x (+9) = 18

2 groups of 9

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