Yes, negative 6 is a rational number.
A rational number is defined as any number that can be expressed as the quotient or fraction of two integers, where the denominator is not zero. In the case of negative 6, it can be written as -6/1. Here, -6 is the numerator (an integer), and 1 is the denominator (also an integer). Since both the numerator and denominator are integers, negative 6 meets the criteria for being a rational number.
Additionally, rational numbers include all whole numbers, negative whole numbers, fractions, and terminating or repeating decimals. Thus, negative 6 is indeed part of the set of rational numbers.