Question 599478
Let {{{ s }}} = the speed of the 2nd car in km/hr
Let {{{ d }}} = distance in km 2nd car travels until it catches 1st car
The 1st car's head start is {{{ 60*2 = 120 }}} km
Start a stopwatch when the 2nd car leaves town
1st car:
{{{ d- 120 = 60*5 }}}
{{{ d = 300 + 120 }}}
{{{ d = 420 }}}km
2nd car:
{{{ d = s*5 }}} 
{{{ 420 = 5s }}}
{{{ s = 84 }}}
the speed of the 2nd car is 84 km/hr