The ion $\mathrm{Co}\left(\mathrm{en}\right){\mathrm{Cl}}_2{\mathrm{Br}}_2^{-}$ is expected to have x geometrical isomers. Find the value of x.

There are four geometrical isomers of the given complex:

1. In one isomer, two Br atoms are Cis to each other.
2. In second isomer, two Br atoms are trans to each other.
3. In third isomer, two Cl atoms are Cis to each other.
4. In fourth isomer, two Cl atoms are trans to each other.