Given:
120 basic channels plus 2 movie channels packages cost $49.
120 basic channels with 4 movie channels packages cost $67.
To find:
The equation represents the linear relationship between price and the number of movie channels.
Explanation:
Let u be the cost of 120 basic channels.
Let v be the cost of a movie channel.
So, the equations are,
[tex]\begin{gathered} u+2v=49.............(1) \\ u+4v=67.............(2) \end{gathered}[/tex]Subtracting (1) from (2), we get
[tex]\begin{gathered} 2v=18 \\ v=9 \end{gathered}[/tex]Substiting v = 9 in equation (1), we get
[tex]\begin{gathered} u+2(9)=49 \\ u+18=49 \\ u=49-18 \\ u=31 \end{gathered}[/tex]So, the equation that represents the linear relationship between price and the number of movie channels is,
[tex]\begin{gathered} Price,\text{ }P=Price\text{ of basic channels+Price of movie channels}\times No.\text{ of movie channels} \\ Price,P=31+9n \end{gathered}[/tex]Where n represents the number of movie channels.
Final answer: The equation is,
[tex]Price=31+9n[/tex]Where n is the number of movie channels.