Help me complete it fast pls

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

What is the 9th term in the geometric sequence described by this explicit formula? an=-6. (2)(n-1) apex

Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9