A national park ranger sitting on a track sees a hedgehog and possum travelling in the same direction down the track. Their distances from the ranger are given by :
Hedgehog - dh = t(40-t)+3 possum dp= 23t-1
where t is the time in minutes since the ranger first saw them and d is the distance in metres from where the ranger is sitting.
At what time after the ranger first saw them are the hedgehot and the possum at the same place on the track?