Question

data was collected on the amount of time that a random sample of 8 students spent studying for a test and the grades they earned on the test. a scatter plot and line of fit were created for the data.

determine the equation of the line of fit.
$y = 5x + 70$
$y = 5x + 80$
$y = 10x + 70$
$y = 10x + 80$

Explanation:

Step1: Identify y-intercept

The line crosses the y-axis at $y=70$, so $b=70$.

Step2: Calculate slope

Use two points on the line, e.g., $(0,70)$ and $(5,100)$.
Slope $m=\frac{100-70}{5-0}=\frac{30}{5}=6$.

Step3: Form line equation

Use slope-intercept form $y=mx+b$.

Answer:

A. $y = 6x + 70$