Question

the scatter - plot shows the association between time elapsed and distance left to go when john drove from his city to city b. what are the slope and the y - intercept of the line of best fit for the scatter - plot?
a. the y - intercept is 80, and the slope is 1
b. the y - intercept is 80, and the slope is - 1
c. the y - intercept is 80, and the slope is - 1/2
d. the y - intercept is 15, and the slope is 1
e. the y - intercept is 15, and the slope is 1/2

Explanation:

Step1: Identify y - intercept

The line crosses y - axis at 80, so y - intercept \(b = 80\).

Step2: Calculate the slope

Pick two points, say \((0,80)\) and \((160,0)\). Slope \(m=\frac{y_2 - y_1}{x_2 - x_1}=\frac{0 - 80}{160-0}=-\frac{1}{2}\).

Answer:

B. The y - intercept is 80 and the slope is - \(\frac{1}{2}\)