Exercise 28 Page 239

To evaluate the given expression for b = -4 and c = 3, first, we should substitute these values into the expression. When multiplying real numbers, the product will be positive if the signs are the same and it will be negative if the signs are different. cc Same Sign & Different Signs (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) We will use the Associative Property of Multiplication to multiply the first two numbers first. There are two negative numbers so the product will be positive.

-6(- 4)

MultNegNegOnePar

- a(- b)=a* b

6* 4

IdPropMult

Identity Property of Multiplication

24

Now we will multiply the remaining two numbers. The result of the first multiplication was positive and the third number is positive, so the final product will be positive.

24(3)

Multiply

Multiply

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