Question

the graph below shows a line of best fit for data collected on the daily profits made by street vendors as a function of the number of customers.
street vendor profits
which of the following is the equation of the line of best fit?
a. $y = 6x + 5$
b. $y = 6x - 30$
c. $y = \frac{3}{5}x - 30$
d. $y = \frac{3}{5}x + 5$

Explanation:

Step1: Find y-intercept

The line crosses y-axis at (0, -30), so b=-30.

Step2: Calculate slope

Pick two points: (0, -30) and (5, 0). Slope $m=\frac{0-(-30)}{5-0}=6$.

Step3: Form equation

Using $y=mx+b$, get $y=6x-30$.

Answer:

B. $y = 6x - 30$