From the first part of your data, we know that
C(x) = mx + 20
we know 2 ordered pairs (3,26) and (4,28)
sub in the first:
26 = 3m+20
3m = 6
m = 2
so C(x) = 2x + 20
Did you notice that the 2nd point was not needed, thus the part "If the customer uses 4 GB, the monthly cost will be $28" is superfluous information.
Use you knowledge about the equation in the form y = mx + b to answer b)
A phone company has a monthly data plan where a customer pays flat monthly fee of $20 and then a certain amount of money per gigabyte (GB) of data used on the phone. If a customer uses 3 GB, the monthly cost will be
$26. If the customer uses 4 GB, the monthly cost will be $28.
a. Find a linear equation for the monthly cost of the data plan as a function of
x, the number of MB used.
C(x) =
b. Interpret the slope and y-intercept of the equation.
1 answer
1 answer