The journalist met a source at the hotel this way he would get facts for an article combined subordinate conjunction into these sentences

The journalist met a source at the hotel in order to get facts for an article.

Explanation:

An independent clause is a clause that can stand alone as a sentence. Every sentence must contain a subject and predicate and express a complete thought.

Dependent (subordinate) clauses are clauses that can't stand alone as sentences because they don't fulfill all of these criteria. Their purpose is to provide additional information about what is stated in the independent clause they are connected to.

Subordinate conjunctions are conjunctions that connect subordinate clauses to independent clauses. The subordinate conjunction that can be used in the given case is in order to. It's used to explain the purpose of the action that takes place in the independent clause.

3 is blunder, i’m not sure about the last one but the first two look correct