Answer:
The original height of the candle is 15 inches
Step-by-step explanation:
Let
x ----> the number of hours
y ----> the height of the candlestick
we know that
The linear equation in slope intercept form is equal to
[tex]y=mx+b[/tex]
where
m is the slope or the unit rate of the linear equation
b is the y-intercept or initial value of the linear equation
In this problem we have
The slope is equal to [tex]m=-0.2\ \frac{in}{h}[/tex]
Is negative because is a decreasing function
we have the ordered pair (8,13.4)
substitute in the equation
[tex]13.4=-(0.2)(8)+b[/tex]
solve for b
Note: In this context the y-intercept is equal to the original height of the candle
[tex]13.4=-1.6+b[/tex]
[tex]b=13.4+1.6[/tex]
[tex]b=15\ in[/tex]
therefore
[tex]y=-0.2x+15[/tex]
