Answer:
The y-intercept of the least squares line is 7 and slope of the line is 1.1. It means x and y are positively related.
Step-by-step explanation:
Least squares : It is an approach to find a regression line such that the sum of squares of residual(difference between estimated point on the line and data point) is minimum.
The given points are (10,10), (20,50), (40,20), and (50,80).
The least squares line is
.... (1)
The general form of least squares line is
.... (2)
where, a is y-intercept and b is slope of the line.
On comparing (1) and (2) we get
It means the y-intercept of the least squares line is 7 and slope of the line is 1.1.
Slope is positive it means x and y are positively related.