can you help me before saturday ?

Question

the student council want to buy vases for the flowers for school prom. a florist, charges a 20$ delivery fee plus $1.25 per vase. a home-decorating store charges $10 delivery fee plus $1.25 per vase.

 

a. the function f(x)= 20 + 1.25x models the cost of ordering x vases from the florist, and the function g(x)= 10 + 1.25x models the cost of ordering x vases from the home - decorating store. what do the graphs of these functions look like ?

 

b. how are the graphs related to each other ?

 

c.how could you modify these functions so that their graphs ae identical ?

 

d. if the florist decided to waive the $20 delivery fee as long as the number of vases ordered was more than 150, how would the graphs of f change ? how would it compare with the graph of the other function?

Answer 1

a). First put the equations in terms you are used too.

f(x) = 1.25x + 20

g(x) = 1.25x + 10

they are linear (straight lines) and they are 10 units apart.

f(x) goes through (0, 20)

and g(x) goes through (0, 10)

f(1) = 1.25 + 20 = 21.25 (1,21.25)

g(1) = 1.25 + 10 = 11.25 (1, 11.25)

There are the 2 point for each function to graph them.

b). The lines are parellel.

c). make the constant equal.  (20 and 10)

d). the function would now be

F(x) >= 1.25(x + 150)

F(x) >= 1.25x + 187.50

It would be the line and all the values above it

It would start at (0, 187.50)