"This is a red apple, not black."
Translation:Ez piros alma, nem fekete.
Is there a difference? Or is one of them preferred? I know that English does weird stuff with articles that other languages find awkward...(mostly it's just that Duo marked me wrong for putting "egy" :/)
Yes, Duo marked me wrong for putting "egy" as well. I am a Hungarian native speaker and can assure you that "egy" is perfectly fine here, used as an indefinite article. The meaning is very slightly different. I will report it.
Adjectives come before the noun that they are modifying. Piros alma, sárga banán, hosszú út, széles folyó, and so on.
If you see what looks like an adjective coming after its noun, then the adjective may be playing the role of the predicate in the sentence. Compare the following:
A piros alma itt van (the red apple is here) vs Az alma piros (the apple is red)
A hosszú út keletre fordul (the long road turns east) vs Az út hosszú (the road is long)
A széles folyó tele van halakkal (the wide river is full of fish) vs A folyó széles (The river is wide.)
Yes, I would say the adjectives in Hungarian are placed exactly like the adjectives in English. That is, in relation to the noun. What can throw you off is the placement of the verb, or the complete lack of it in some cases (the case of the omitted "van"), making the adjective (which is the predicate in that case) appear immediately after the noun.
But an adjective modifying a noun, ie. an attributive adjective, will ALWAYS be in front of the noun, not after it. Nothing like they do it in Spanish.
I think that this is not normally used in this case. Of course there can be some exceptions, I found these two:
Vörös húsú alma, vörösbelű alma (specific kinds of an apple, typically with red pulp): http://www.gyulavaros.hu/gyulai-gasztronauta/voros-husu-alma, http://gyumolcspedia.hu/vorosbelu-alma
Vörösalma (Hungarian version of the village name situated in NE Slovakia): https://hu.wikipedia.org/wiki/V%C3%B6r%C3%B6salma