Question

lynn is tracking the progress of her plants growth. today the plant is 5 cm high. the plant grows 1.5 cm per day. suppose Lynn's plant grewn to a height of 30.5 inches how many days will have passed

Answer 1

We have that the plant start with 5 cm high and it grows 1.5 cm per day, then the equation to model this situation is:

$y=1.5x+5$

where x represents the days that passes and y represents the height of the plant.

Now, let's convert 30.5 inches to cm:

$\begin{gathered} 1in=2.54\operatorname{cm} \\ \Rightarrow(30.5)\cdot(2.54)=77.47\operatorname{cm} \end{gathered}$

then, suppose that Lynn's plant grew to a height of 77.47 cm, then we have to make y = 77.47 and solve for x to get the following:

$\begin{gathered} y=77.47 \\ \Rightarrow77.47=1.5x+5 \\ \Rightarrow77.47-5=1.5x \\ \Rightarrow72.47=1.5x \\ \Rightarrow x=\frac{72.47}{1.5}=48.3 \\ x=48.3 \end{gathered}$

therefore, it will take approximately 48 days to the plant to grow to a height of 30.5 inches