Question

question 2 of 10
a set of data points has a line of best fit of $hat{y}=2.5x - 1.5$.
what is the residual for the point $(4,7)$?
a. 1.5
b. 8.5
c. 7
d. -1.5

Explanation:

Step1: Predict y - value

Substitute $x = 4$ into $\hat{y}=2.5x - 1.5$. So, $\hat{y}=2.5\times4-1.5$.
$\hat{y}=10 - 1.5=8.5$.

Step2: Calculate residual

The formula for residual is $e=y-\hat{y}$. Given the point $(4,7)$, where $y = 7$ and $\hat{y}=8.5$. Then $e=7 - 8.5=-1.5$.

Answer:

D. -1.5