Question

Two cell phone companies have different rate plans. Runfast has monthly charges $10 plus $4 per gig of data. B A &D’s monthly charge is $6 plus $6 per gig of data. Your task, is to determine under what circumstances each company has the better pricing. You will derive and solve a set of equations, graph those equations, and evaluate the meanings for these events.

Answer 1

g is gigs of data
R is first company, B is the second
R = 4 g + 10
B = 6 g + 6
cost the same when
10 + 4 g = 6 + 6 g

if more data, R is cheaper (lower slope)

Answer 2

cost1 = 10 + 4g
vs
cost2 = 6 + 6g

Your "task" is to simply solve 6+6g = 10+4g to get the break-even point.

Just graph the two equations as if they were
y = 4x + 10 and y = 6x + 6 to illustrate.

http://www.wolframalpha.com/input/?i=plot+y+%3D+4x+%2B+10,+y+%3D+6x+%2B+6

looks like a "much ado about nothing"

Answer 3

Thanks

Answer 4

Also,
4. (1 pt) Why don’t the lines start at the origin?
5. (1 pt) What is the meaning to each of the y-intercepts?
6. (2 pts) Which company has the better deal for customers that don’t us much data? How do you know? Be sure to include how your response relates to the point of intersection.
7. (2 pts) At what point are the plans the same amount? How do you know?
8. (2 pts) Which company has the better deal for customers that use a lot of data? How do you know? Be sure to include how your response relates to the point of intersection.

Answer 5

please help? I need to know how to use the substitution method to figure out the equation