Chapter 9 - Basic Algebra - 9.3 Multiplying and Dividing Signed Numbers - 9.3 Exercises - Page 647: 101

(a) $$8 \times (-1) = -8 \\88 \times (-1) = -88 \\888 \times (-1) = -888$$ (b) $$-8 \times (-1) = 8 \\-88 \times (-1) = 88 \\-888 \times (-1) = 888$$ When $-1$ is multiplied to a signed number, the product is the signed number's opposite or additive inverse.

(a) Product of a positive number and $-1$ examples: $$8 \times (-1) = -8 \\88 \times (-1) = -88 \\888 \times (-1) = -888$$ (b) Product of a negative number and $-1$ examples: $$-8 \times (-1) = 8 \\-88 \times (-1) = 88 \\-888 \times (-1) = 888$$ From the examples above, it can be seen that when $-1$ is multiplied to a signed number, the product is the signed number's opposite or additive inverse.