Question

this question has two parts. first, answer part a. then, answer part b.
part a
the scatter plot shows the amount of time different students spend studying for a test and their test score.
part a
which equation best represents the line that is drawn?
$y = 1.33x - 40$
$y = 1.33x + 40$
$y = 0.66x - 40$
$y = 0.66x + 40$

Explanation:

Step1: Analyze the y-intercept

The line crosses the y-axis at (0, 40), so the y-intercept \( b = 40 \). The equation of a line is \( y = mx + b \), so the equation should have \( +40 \), eliminating options with \( -40 \).

Step2: Estimate the slope

Take two points, e.g., (0, 40) and (30, 80). Slope \( m=\frac{80 - 40}{30 - 0}=\frac{40}{30}\approx1.33 \). So the slope is approximately 1.33 and y-intercept 40, giving \( y = 1.33x + 40 \).

Answer:

\( y = 1.33x + 40 \) (the second option: \( y = 1.33x + 40 \))