Question 1025328
<pre>
                  rate        time        distance
GOING              12          x            d
RETURNING           8          y            d
total                          10          2d
</pre>




Use basic rule RT=D and apply to the information in the data table.


{{{system(12x=d,8y=d,x+y=10,12x+8y=2d)}}}


Or you might choose equating two d expressions.
{{{highlight(system(12x=8y,x+y=10))}}}
and this is the system you would want to solve.  You can then compute d from it.  Then compute 2d.