Question 830443
r the speed for the bus
h the time in HOURS for the bus
48 minutes is {{{4/5}}} hour



________________speed_______________time_____________miles
Car_____________r+10________________h-(4/5)________240
Bus______________r___________________h_______________240


You could generalize everything and solve this all in symbols before using given values.  Try this:


________________speed_______________time_____________miles
Car_____________r+v________________h-p_______________d
Bus______________r___________________h_______________d


Your equations from this begin as:
{{{(r+v)(h-p)=d}}}  and {{{rh=d}}};
If you take the simpler equation as {{{h=d/r}}}, and then start working with the car's equation, substituting for h and for rh, will allow you to get a quadratic equation, a very simple-looking one, in r.  You could then use the general solution for a quadratic equation to get a formula for r.


...  just remember what your given values were and what you wanted to find.