Sin (x-20) = 1/root2

This question is confusing me.

=> x - π/9 = π/4 + 2kπ, where k is an integer or x - π/9 = 3π/4 + 2kπ, where k is an integer = > x = 13π/36 + 2kπ, where k is an integer or x = 31π/36 + 2kπ, where k is an integer;