Exercise
The equation 15x = 6 mod 9 has (modulo 9)
no solutions
1 solution
2 solutions
3 solutions
Note that 15 = 6 mod 9
You can compute the number of solutions using the gcd
You can compute the number of solutions using the gcd
Correct, there are 3 = gcd(15,9) solutions, namely x = 1, 6 or 11 mod 9.