Question

what is the main purpose of drawing a line of best fit on a scatterplot?
○ to show the general trend of the data
○ to represent the maximum value
○ to connect all the points
○ to highlight outliers

question 4
5 pts
what does the regression line y=0.25x+5 predict for y when x=8?
○ 5
○ 2
○ 8
○ 7

Explanation:

First Question (Multiple Choice)

A line of best fit on a scatterplot is used to show the overall pattern or trend (positive, negative, or no trend) in the data. It does not connect all points (as points are scattered), represent maximum value, or highlight outliers. So the correct option is the one about showing the general trend.

Step1: Substitute \( x = 8 \) into the regression line equation \( y = 0.25x + 5 \)

\( y = 0.25\times8 + 5 \)

Step2: Calculate \( 0.25\times8 \) first

\( 0.25\times8 = 2 \)

Step3: Add 5 to the result

\( y = 2 + 5 = 7 \)

Answer:

To show the general trend of the data

Second Question (Calculation)