Final answer:
When adding two negative integers, like (-36) and (-21), the result is also negative. You add the absolute values (36 and 21) to get 57 and then apply the negative sign, yielding -57 as the final answer.
Step-by-step explanation:
To add the integers (-36)+(-21), you follow the rule where two negative numbers added together result in a negative number. You simply add the absolute values of the numbers and keep the negative sign, because when two negative numbers add, the answer has a negative sign.
The absolute value of -36 is 36, and the absolute value of -21 is 21. Adding these two numbers: 36 + 21 equals 57. Therefore, the sum of (-36)+(-21) is the negative of that sum, which is -57.