You can
put this solution on YOUR website!For both,

Each has their own rates, times and distances, so

Tony's equation

Gerry's equation
Each bikes to the others house and they leave at the same time, so
For Tony,

hrs
and, for Gerry,

hr
Comparing these, with LCD

So, Tony got to Gerry's house

hrs quicker
than Gerry got to Tony's house.
-------------------
Now, they turn around and head back toward eachother.
If they left at the exact same time, the elapsed
time for each until they met would be the same

, but Tony gets a head start.
-------------------
Assume I have a stopwatch and I'm in a helicopter overhead
so I can see both of them. I'll start the stopwatch when
Gerry turns around

hr after Tony has turned around.
If Gerry's time to where they meet from Tony's house is
then Tony's time from Gerry's house is

--------------------
Now my equations are

km
where these are the distances each travel to where they meet
(1)

(2)

rewriting (1)
(1)

Substitute (2) in (1)

hr

hrs or

min
------------------
The distance Tony travels is the distance from Gerry's
house when they meet
(1)

km
They meet 7 km from Gerry's house
check answer:
(2)

and

km

OK