. Could someone please explain this to me in detail. I am very confused. Thank you so much!. . A candle is 17 inches tall after burning for 3 hours. after 5 hours it is 15 inches tall. Write a linear equation to model the relationship between height H of the candle, and T time. predict how tall the candle will be after burning 8 hours.
We can translate the given data into points (hrs,inches). Hence, we have points (3,17) and (5,15). The rate at which the candle shortens is (15-17)/(5-3) equal to 1 inch per hour. Substituting this slope to the equation (y2-y1)= m(x2-x1) we have y-17= -1*(x-3) or y = -x + 20 where y is the length of the candle and x is the hours.
The generic equation of the line is:
\(H-H0 = m (T-T0)\)
Where,
m: slope of the line
(T0, H0): ordered pair belonging to the line.
The slope of the line is:
\(m =\frac{H2-H1}{T2-T1}\)
Substituting values we have:
\(m =\frac{15-17}{5-3}\)
Rewriting:
\(m =\frac{-2}{2}\)
\(m = -1\)
Then, choosing an ordered pair we have:
\((T0, H0) :( 5, 15)\)
Substituting values we have:
\(H-15=-(T-5)\)
Rewriting the equation:
\(H-15=-T+5\)
\(H=-T+5+15\)
\(H=-T+20\)
Then, for 8 hours we have:
\(H=-8+20\)
\(H=12\)
Answer:
a linear equation to model the relationship between height H of the candle, and T time is:
\(H=-T+20\)
the candle will be 12 inches after burning 8 hours