Answer:
Step-by-step explanation:
let us model the cost
let the cost be y and the number of movie channel be x
for 3 comcast
y=50+5x-----1
and for Xfinity
y=41+6.5x-------2
to solve for the number of movie channel so that the two (3 comcast and Xfinity) will pay the same, we need to equate 1 and 2
50+5x=41+6.5x
50-41=6.5x-5x
9=0.5x
x=9/0.5
x=18