As equipas empataram.

Because equipa is a feminine noun in Portuguese.

• a equipa = the team
• as equipas = the teams

So the article has to match the noun:

• a / as for feminine
• o / os for masculine

English does not usually show grammatical gender like this, but Portuguese does.

In this sentence, the plural is shown in two places:

• as = plural feminine article
• equipas = plural noun

The noun equipa becomes equipas by adding -s, which is a very common way to form the plural in Portuguese.

Compare:

• a equipa empatou = the team drew
• as equipas empataram = the teams drew

Empataram is the 3rd person plural of the pretérito perfeito simples of empatar.

In practical terms, that means it is a completed past action:

• empatam = they draw / they tie
• empataram = they drew / they tied

So the sentence refers to something that happened and is finished.

Because empatar is an -ar verb, and in the preterite, the 3rd person plural ending for regular -ar verbs is -aram.

Pattern:

• falar → falaram
• jogar → jogaram
• empatar → empataram

This ending tells you the subject is they or you plural in a formal sense, though here the subject is clearly as equipas.

Mostly, yes. Empatar is very commonly used in sports or competitions to mean that both sides finished with the same result.

For example:

• two football teams finish 1–1
• two players finish with the same score

The related noun is empate = a draw / a tie.

So:

• As equipas empataram.
• Houve um empate.

This is an important difference.

• empataram = they ended in a draw / they drew
• estavam empatadas = they were tied

So:

• empataram focuses on the result of the match
• estavam empatadas focuses on the state or situation at a certain moment

Example:

• Ao intervalo, as equipas estavam empatadas. = At half-time, the teams were tied.
• No fim, as equipas empataram. = In the end, the teams drew.

Also notice empatadas agrees with equipas, which is feminine plural.

Yes. Portuguese often allows the subject to be left out if it is clear from context.

So Empataram. can mean They drew.

The verb ending -aram already tells you the subject is plural. However, without context, you would not know exactly who they are. Using as equipas makes it explicit.

In Portuguese, using the definite article is very natural when talking about specific, known teams.

So as equipas often means the teams in a normal, natural way.

If you remove the article and say Equipas empataram, it can sound more like:

• a headline
• a very general statement
• a less natural isolated sentence in everyday speech

So As equipas empataram is the normal full sentence.

In European Portuguese, the words often link together.

A useful approximation is:

• as before a vowel often sounds like az
• final -s in equipas also links to the next vowel and can sound like z

So the sentence may sound roughly like:

az equipaz empataram

A few extra pronunciation notes:

• equipa is stressed on -qui-
• empataram is stressed on -ta-
• the final -am in European Portuguese is nasal

You do not need perfect IPA at the start, but it helps to know that the written s does not always sound like English s.

Yes, equipa is the normal word in Portugal for team.

This is one of the differences between European and Brazilian Portuguese:

• Portugal: equipa
• Brazil: often time, and also equipe in some contexts

So in Portugal, As equipas empataram sounds completely standard and natural.