Unluckily
undecided
The prefix is in- The opposite of conspicuous (easily seen) is inconspicuous.
The prefix you would add to "ordinary" to make it the opposite is "extra-". This would create "extraordinary," which means exceptional or remarkable.
The prefix added to "justice" to make it the opposite is "in-". This forms the word "injustice," meaning the lack of fairness or a violation of rights.
Unfashionable you just add a prefix un, meaning not
A prefix is an added beginning to a word, which often changes its meaning. If you add the prefix "mis" to spelled, you get the word "misspelled", which means spelled incorrectly. This is, indeed, the antonym, or opposite, of spelled. disable, unable, and enable
The prefix you can add to charge is "re-," as in "recharge."
inaddable. The prefix in is used and also the suffix Able.
To add two integers with opposite signs . . . -- Ignore the signs, and write the difference between the two numbers. -- Give it the same sign as the larger original number has.
Add (something) at the beginning as a prefix or introduction.
"Im" is a common prefix in itself, you don't add a prefix to a prefix.
In the word "inform", in- is a prefix. You could add the prefix mis- to it to get misinform.