NO2− :Due to sp2 hybridisation of N-atom and the presence of one lone pair on it,NO2− has angular shape.
SO2 : Due to the presence of one lone pair of electrons in one of the three sp2− hybrid orbitals and sp2 hybridisation of S or S+ atom,SO2 molecule has aguilar (V-shaped) structure
NO2+:Due to sp hybridisation of N+,NO2+ ion has linear shape