[tex]\huge\fbox{Hi~there!}[/tex]
Remember, a number's additive inverse is simply its opposite.
Let's say we have a number a.
The opposite of a is -a, and the opposite of -a is a.
Thus, the additive inverse of
[tex]\displaystyle\frac{7}{10}[/tex] is
[tex]\displaystyle-\frac{7}{10}[/tex]
Hope it helps.
~Just a felicitous girl
#HaveAnAmazingDay
Feel free to ask if you have any doubts.
[tex]\bf{-MistySparkles^**^*[/tex]