Question

Find all x ∈ Z satisfying each of the following equations.3x = 2 (mod 7)

Answer 1

7x−3=7k,x=7k+3,k∈ℤ

Explanation:

3x ≡ 2 (mod 7)

3 is a solution, since 3×3−2=7.

All solutions are 3+7ℤ

y=3x−2/7=3(x−3)+7/7=3(x−3)/7+1

7x−3=7k,x=7k+3,k∈ℤ