What is next number after 2 7 8 3 12 9

Which pair of angles are vertical angles? ∠1 and ∠4∠1 and ∠2∠2 and ∠4∠2 and ∠3more than one answer.

Statement: if two points are given, then exactly one line can be drawn through those two points. which geometry term does the statement represent? defined term postulate theorem undefined term

Find the pattern and use it to list the nth term in the sequence. 6, 12, 20, 30, 42, 56, the nth term of the sequence is