HiSET: Math : Identify lines of best fit

Example Questions

Example Question #1 : Identify Lines Of Best Fit

Determine the linear regression line for the following paired data:

Explanation:

The formula for a regression line for a set of paired data is the line of the equation

,

where

and

.

, the number of pairs.

is the sum of the  values:

is the sum of the  values:

is the sum of the squares of the  values:

is the sum of the  products:

Substituting:

and  are the arithmetic means of the  and  values, respectively - the sums divided by the number of values:

The equation of the linear regression line is .

Example Question #2 : Identify Lines Of Best Fit

Determine the linear regression line for the following paired data:

Explanation:

The formula for a regression line for a set of paired data is the line of the equation

,

where

and

.

, the number of pairs.

is the sum of the  values:

is the sum of the  values:

is the sum of the squares of the  values:

is the sum of the  products:

Substituting:

and  are the arithmetic means of the  and  values, respectively - the sums divided by the number of values:

The linear regression line is the line of the equation .