Answer :
The opposite of a number is defined as its additive inverse, which is the number that, when added to the original, equals zero. In other words, for any number [tex]$a$[/tex], its opposite is [tex]$-a$[/tex] because
[tex]$$
a + (-a) = 0.
$$[/tex]
Given that [tex]$a = 145$[/tex], the opposite is calculated as
[tex]$$
-1 \times 145 = -145.
$$[/tex]
Thus, the opposite of [tex]$145$[/tex] is [tex]$\boxed{-145}$[/tex].
[tex]$$
a + (-a) = 0.
$$[/tex]
Given that [tex]$a = 145$[/tex], the opposite is calculated as
[tex]$$
-1 \times 145 = -145.
$$[/tex]
Thus, the opposite of [tex]$145$[/tex] is [tex]$\boxed{-145}$[/tex].