Work Step by Step
The opposite of a real number $a$ is $-a$. For any two numbers $a$ and $-a$, $a+(-a)=0$. That is, the sum of a number and its opposite is equal to 0. Therefore, the opposite of 51 is -51, because $51+(-51)=0$.
You can help us out by revising, improving and updating this answer.Update this answer
After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.