Question Number 198646 by Engr_Jidda last updated on 22/Oct/23
Answered by mr W last updated on 23/Oct/23
$${story}\:{is}\:{silly},\:{but}\:{solution}\:{is}\:{easy}! \\ $$$$ \\ $$$${girl}:\:{a}\left({t}\right)=\mathrm{1}×{t}={t} \\ $$$${boy}:\:\:{b}\left({t}\right)=\mathrm{5}×{t}=\mathrm{5}{t} \\ $$$${distance}\:{between}\:{them}: \\ $$$${c}\left({t}\right)=\sqrt{{a}^{\mathrm{2}} +{b}^{\mathrm{2}} }=\sqrt{\mathrm{26}}{t} \\ $$$$\frac{{dc}\left({t}\right)}{{dt}}=\sqrt{\mathrm{26}}\:{ft}/{s} \\ $$$$\Rightarrow{they}\:{are}\:{separating}\:{at}\:{a}\:{rate} \\ $$$${of}\:\sqrt{\mathrm{26}}\:{ft}/{s}\:{at}\:{any}\:{time}. \\ $$
Commented by Engr_Jidda last updated on 23/Oct/23
$${thank}\:{you}\:{sir} \\ $$