Respuesta :

Answer:

35mins

Step-by-step explanation:

Can you hear me now cost function: y=0.15x+50.75

24 Hour Calls cost function: y=0.9x+24.5

Set two equations equal to each other because we want to find the time (x value) that make the cost  (y-value) equal

0.15x+50.75=0.9x+24.5

0.75x=26.25

x=35mins

35 mins is probably the answer