11. Let complex numbers $z_{1}, z_{2}$ satisfy $z_{2}=z_{1} i-2$, and $z_{1}$ corresponds to point $Z_{1}$ on the curve $|z-2|+|z+2|=10$ in the complex plane. Then the trajectory equation of $z_{2}$ in the complex plane, corresponding to point $Z_{2}$, is $\qquad$
(in the original Cartesian coordinate system of the complex plane, express using a common equation)
11. $\frac{(x+2)^{2}}{21}+\frac{y^{2}}{25}=1$