Answer:
angles 4 and 6 are congruent
Explanation:
The statements that should be used to prove that angles 4 and 6 are congruent are:
"Angles 4 and 3 form a linear pair."
"Angles 3 and 1 are congruent as vertical angles."
These statements establish the relationships between the angles in a way that leads to the conclusion that angles 4 and 6 are congruent.