  We present Australia Telescope Compact Array radio continuum observations of
the quasar/galaxy system HE0450-2958. An asymetric triple linear morphology is
observed, with the central radio component coincident with the quasar core and
a second radio component associated with a companion galaxy at a projected
distance of 7kpc from the quasar. The system obeys the far-infrared to radio
continuum correlation, implying the radio emission is energetically dominated
by star formation activity. However, there is undoubtedly some contribution to
the overall radio emission from a low-luminosity AGN core and a pair of radio
lobes. Long baseline radio interferometric observations of the quasar core
place a 3sigma upper limit of 0.6mJy at 1400MHz on the AGN contribution to the
quasar's radio emission; less than 30% of the total. The remaining 70% of the
radio emission from the quasar is associated with star formation activity and
provides the first direct evidence for the quasar's host galaxy. A re-anlaysis
of the VLT spectroscopic data shows extended emission line regions aligned with
the radio axis and extended on scales of ~20kpc. This is interpreted as
evidence for jet-cloud interactions, similar to those observed in radio
galaxies and Seyferts. The emission lines in the companion galaxy are
consistent with radiative shocks and its spatial association with the eastern
radio lobe implies large-scale jet-induced star formation has played a role in
this galaxy's evolution.
