In $\mathrm{\text{C}}{\mathrm{\text{O}}}_2$, C-atom is $\text{s}\text{p}$-hybridised, thus it has linear structure. In $\mathrm{\text{X}}\mathrm{\text{e}}{\mathrm{\text{F}}}_2$, Xe is $\text{s}{\text{p}}^3\text{d}$ hybridised with three lone-pairs of electrons on equatorial positions. This mtextnimtextses repulsion, hence it has also linear structure.