A satellite television plan costs $26 each month. For an extra amount each month, the satellite television...

A satellite television plan costs $26 each month.
For an extra amount each month, the satellite television plan can come with 5 movie channels. With the extra data, the plan will cost $720 over 18 months.
How much do the extra 5 movie channels cost each month?
Extra 5 movie channels monthly cost = $____