Answer:
y= 7.5x+45
Explanation:
Let your data consumption in terms of GB be represented by x. Since you must first pay access fee and each data costs $7.5 per GB then it means in case you need 1 GB data you will pay 7.5(1)+45, similarly, when you need 2 GB data you will pay 7.5(2)+45, for 3 GB you will also pay 7.5(3)+45. For n GB you will pay 7.5(n)+45 hence the equation representing your data expenditure will be y=7.5x+45 where y is the total expenditure.