Question 187378
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Working Eqn----->{{{Speed=Distance/time}}}, and we'll see the 2 cars below:
{{{drawing(300,300,-.5,12,-.5,1,locate(0,.5,Car2=70mph),locate(7.5,.5,Car1=60mph),green(line(.5,.25,7.5,.25)),red(locate(2.5,.25,Apart=80miles)),arrow(-4,.1,2,.1))}}}
From our Eqn we get, Distance=Speed*time
Equating the 2 Cars and remember <font color=red>to add 80 miles</font> to Car{{{1}}}:
{{{S[2]*t=S[1]*t+80miles}}} --->{{{70*t=60*t+80}}}
{{{70t-60t=80}}}---->{{{10t=80}}}---->{{{cross(10)t/cross(10)=cross(80)8/cross(10)}}}
{{{red(t=8hrs)}}}--> After 8 hrs they will be at the same Distance. Let's check,
Car{{{1}}}: {{{D[1]=60*8+80=480+80=560miles}}}
Car{{{2}}}: {{{D[2]=70*8=560 miles}}}
Therefore, <font color=red>AFTER 8 hrs</font>, Car{{{2}}} with Speed of 70mph will overtake Car{{{1}}}.


Thank you,
Jojo</font>