Multiplication of Integers is similar to multiplication of whole numbers (both positive)
except the sign of the product needs to be determined.
If both factors are positive, the product will be positive.
If both factors are negative, the product will be positive.
If only one of the factors is negative, the product will be negative.
In other words, if the signs are the same the product will be positive, if they are
different, the product will be negative.