Hello everybody!

I am trying to solve the following question: Find $\displaystyle (-11-2i)^{1/3}$

I did the following: $\displaystyle (-11-2i)^{1/3}=(a+bi)$ and I'll get $\displaystyle a^{3}-3ab^{2}=-11$ and $\displaystyle 3a^{2}b-b^{3}=-2$

If I put $\displaystyle a=1$ I can solve this question. But I would like to know how to solve the system above.

Thanks in advance!