Question

If you multiply four negative numbers, what is the sign of the product?

Answer 1

Answer:

positive

Step-by-step explanation:

(-a) (-a) (-a) (-a) = a

(-a)(-a) = a

a (-a) = -a

-a (-a) = a --> positive sign

Answer 2

If you multiply four negative numbers, what is the sign of the product?

You can test this with numbers, the easiest with -1:

(-1)(-1)(-1)(-1) = (1)(-1)(-1) = (-1)(-1) =  1

General:

(-a)(-b)(-c)(-d) = abcd

The sign of the product of four negative numbers is positive.

If you multiply five negative numbers, what is the sign of the product?

Testing with -1:

(-1)(-1)(-1)(-1)(-1) = (1)(-1)(-1)(-1) = (-1)(-1)(-1) = (1)(-1) -1

General:

(-a)(-b)(-c)(-d)(-e) = -abcde

The sign of the product of five negative numbers is negative.

General rule: The product of an even number of negative numbers is positive. The product of an odd number of negative numbers is negative.