If 7n+1 is a multiple of 4, then what is n mod 4
???
help? Thank you!
No one got an answer?
7n+1 = 0 (mod 4)
4n+3n+1 = 0 (mod 4)
3n+1 = 0 (mod 4)
3n = -1 (mod 4)
3n = 3 (mod 4)
n = 1 (mod 4)
+169 
