I was marked wrong for "Ini tidak restoran." Is this wrong?
From what I read online, tidak is used with negation of words except for nouns. Bukan is used to negate nouns. But technically I would assume a native speaker would still understand you regardless. In English both words translate to no or not.
"Sir, this is a Wendy's"
Please have a look here :
Negation: Tidak, bukan, jangan, belum, Tips & Notes, Addendum.