Given:
A number is 400.
To find:
The additive inverse of 400.
Solution:
We know that the sum of a number and its additive inverse is 0.
If "a" is number and "b" is its additive inverse, then
[tex]a+b=0[/tex]
Let x be the additive inverse of 400. Then,
[tex]400+x=0[/tex]
Subtract both sides by 400.
[tex]400+x-400=0-400[/tex]
[tex]x=-400[/tex]
Therefore, the additive inverse of 400 is [tex]-400[/tex].