Given:
Cost of 1 digital song = $1.05
Cost of 2 digital song = $2.10
Cost of 5 digital song = $5.25
To find:
The equation and the cost of 25 downloaded digital songs.
Solution:
Let us take two points (1, 1.05) and (2, 2.10).
Here
Slope:
m = 1.05
Using point-slope formula:
Add 1.05 on both sides, we get
Here x is the independent variable and c is the dependent variable.
So that substitute x = n and y = c.
The equation is c = 1.05 n.
Substitute n = 25 in the equation.
The cost of 25 songs is $26.25.