Which of the following products will result in an answer less than zero?

(-1) (-1)

(-2) (-10)

(4) (9)

(-4) (7)

First, it is important to understand what happens to the sign of a product of two numbers depending on whether the two numbers are positive or negative. If you multiply two positive numbers, the product is positive; if you multiply a positive number and a negative number, the product is negative; if you multiply two negative numbers, the product is positive.

Since the first three choices would all result in a positive product, the correct choice is (-4) (7) because it would result in - 28 which is below zero.