Question

A researcher surveyed 8 people to see if there is a

relationship between years of education and starting
salaries. The data points are shown on the graph.
Which best represents the equation of the trend line
shown on the graph? (Note that the graph has a break
on the x-axis.)
O y = 0.25x + 15
O y = 0.25x + 17.5
* y = 1.25x - 10
O y = 1.25x + 7.5

Answer 1

`y=1.25x+7.5`

Explanation:

We can see that the trend line is the line of best fit to the data points.

The equation of a straight line is given by:

y = mx + b:

where y, x are variables, m is the slope of the line and b is the y intercept.

From the graph, we can see that the line passes through the points (10, 20) and (14, 25). Therefore the equation of the line is given by:

`y-y_1=(y_2-y_1)/(x_2-x_1) (x-x_1)\\\\y-20=(25-20)/(14-10)(x-10)\\\\y-20=1.25(x -10)\\\\y-20=1.25x-12.5\\\\y=1.25x+7.5`