Answer:
Slope = - 20; intercept, c = 100
y = - 20x
Step-by-step explanation:
The slope (s) = Rise / Run
using the pairs : (0, 100) and (5, 0)
x1 = 0 ; y1 = 100 ; x2 = 5 ; y2 = 0
Rise = (y2 - y1) = (0 - 100) = - 100
Run = (x2 - x1) = (5 - 0) = 5
Slope = - 100 / 5
Slope = - 20
Using the slope intercept relation :
y = mx + c
m = slope ; c = intercept
y = - 20x + c
Using the point (4, 20) to find c
20 = - 20(4) + c
20 = - 80 + c
20 + 80 = c
100 = c
Hence, c = 100
Slope, m = number of songs downloaded per week
c = Total number songs at week 0
The equation expressed in slope intercept form:
General form:
y = mx + c
m = - 20 ; c = 100
y = - 20x + 100
