Question

The table gives two options for online music clubs which is also given by the system of equations:

y = 0.4x + 15 and y = 0.2x + 25

For what number of songs will the monthly charge be the same?

Answer 1

x = 50, y = 35

Explanation:

Solve this system of linear equations by using substitution. Equate the two equations to one another, thus eliminating y:

0.4x + 15 = 0.2x + 25

subtract 0.2x from both sides, obtaining: 0.2x + 15 = 25, or, after combining the constants, 0.2x = 10.

Finally we divide both sides by 0.2, which results in x = 50.

Use the first equation to find y: y = 0.4(50) + 15 = 20 + 15 = 35

Answer 2

50 songs at $35

Explanation: