Question

What is the equation of this trend line enter your answers by filling in the Box N= __ M+_

Answer 1

`\begin{gathered} \text{The trend line equation is;} \\ N=\text{ -2m + 110} \end{gathered}`

Here, we want to get the equation of the trend line

Since the trend line is linear, it follows that the equation of the line can be written in the form;

`y\text{ = mx + b}`

where m is the slope and b is the y-intercept

We can easily get the y-intercept from the graph

The y-intercept is at 110

What is left is to get the slope

To get the slope, we select a point on the trend line

The point we have selected is (30,50)

Simply substitute 30 for x and 50 for y

We have this as;

`\begin{gathered} 50\text{ = 30m + 110} \\ 30m\text{ = -110+50} \\ \\ 30m\text{ = -60} \\ \\ m\text{ = }(-60)/(30)\text{ = -2} \end{gathered}`

So the equation of the thread line would be;

`N=\text{ -2m + 110}`