Question

5 x -8 x 2

What is the product?
Suppose he found the opposite of the correct product. Describe and error he could have made that resulted in that product.

Answer 1

-80

If I found the opposite I probably did not take into account the negative sign with 8

Explanation:

5 x -8 is -40 A positive x a negative is a negative.

-40 x 2 = -80 A negative times a positive is a negative.

Count the negative signs in a multiplication problem. If you count and odd number the answer will be negative. If you count an even number, your answer will be positive.

Answer 2

The product is -80

If he found the opposite of -80 which is 80, he didn’t take notice of the negative sign, which is important.

Explanation:

5 x -8 = -40

-40 x 2 = -80