What is the result when adding two negative numbers together?

When two negative numbers are added together, the result is indeed negative. This occurs because adding two numbers signifies moving further in the direction of the negative axis on a number line. For example, if you add -3 and -5, you are effectively moving three units left from zero to -3 and then an additional five units left to -8. The sum of -3 and -5 results in -8, which is a negative number.

Thus, the fundamental rule in arithmetic regarding the addition of negative integers holds true: the more negative the numbers you add, the more negative the sum becomes. This principle is essential for understanding the behavior of numbers in various mathematical contexts, including algebra and calculus, making this concept fundamental for students in the mathematical domain.