Question 949251
Rate x Time= Distance
{{{9*t[1]+12*t[2]=10}}}
{{{t[1]+t[2]=1}}}
So then,
{{{t[1]=1-t[2]}}}
Substituting into the first equation,
{{{9(1-t[2])+12t[2]=10}}}
{{{9-9t[2]+12t[2]=10}}}
{{{3t[2]=1}}}
{{{t[2]=1/3}}}
So then,
{{{t[1]+1/3=1}}}
{{{t[1]=2/3}}}
2/3 hr(40 min) at 9 mph and 1/3 hr(20 min) at 12 mph