Answer:
B. y = 60x - 150
Explanation:
From week 1 to week 2 he earn -30 - (-90) = $60
From week 2 to week 3 he earn 30 - (-30) = $60
This profit is repeated every week, and 60 represent the slope of the line that relates y and x.
Then, the y value for week 0 is -150, in this way:
From week 0 to week 1 he earn -90 - (-150) = $60
the same value as before is satisfied. -150 is the y-intercept of the line (the y value when x = 0). Therefore, the equation is:
y = slope*x + y-intercept = 60x - 150