The cost of joining a DVD club and buying DVDs is a linear function of the number of DVDs bought. The cost of 3, 5, and 7 DVDs is shown in the table. Identify the equation in slope-intercept form that represents the function.

Answer:
A. y = 3x + 3
Step-by-step explanation:
Slope = change in y / change in x
From 3 to 5 (x) = +2
From 12 to 18 (y) = +6
slope, m = 6/2 = 3
Using point slope form
y - y1 = m (x - x1)
y - 12 = 3 (x - 3)
y - 12 = 3x - 9
y = 3x -9 + 12
y = 3x + 3