Your cell phone company charges $120 for 2 months, $360 for 6 months and $480 for 8
months, what’s the variable?

60 would be the variable
because x would be the amount of months while 60 is the cost per every month and y would be the cost overall therefore you could do

60x=y

this is a valid equation bc you would take the amount of months you would like to purchase and plug it in for x then multiple your x value by 60 to get your y value or your price