Solve x+1≡0(mod2)x + 1 \equiv 0 \pmod 2x+1≡0(mod2).
x≡0(mod2)x \equiv 0 \pmod 2x≡0(mod2)
x≡1(mod2)x \equiv 1 \pmod 2x≡1(mod2)
xxx can be any number
No solution