2. I can only assume you mean $\sin{(x - 10)} = 0$. Inverse sine of 0 is equal to 0, and you should know that at $\pi$ and $2\pi$ the sine function is equal to zero. so $x = 10$, $\pi + 10$ and $2\pi + 10$
You may need your answers in the range $0 \leq x \leq 2\pi$ which can be done by subtracting multiples of $2\pi$ from the above answers.