Question

A store offers packing and mailing services to customers. This table is given to customers to help them estimate the cost of shipping a box based on its weight in pounds, and a flat rate of $5 for packing.

Which equation represents the shipping cost as a function of x, the weight in pounds?

a. f(x) = 2.25x + 5
b. f(x) = 3.5x + 4
c. f(x) = 4x + 9
d. f(x) = 9x + 14

Answer 1

@ganeshie8 @SolomonZelman

Answer 2

@triciaal

Answer 3

Lets plug in 4 and 8 into A and see if it works and gets us 14 and 23 respectively.

Answer 4

2.25(4)+5=9+5=14
now plug in 8
2.25(8)+5=18+5=23
So A is your answer

Answer 5

Also you can realize that it says a flat rate of 5 dollars. So 5 is a constant or C in the formula y=mx+c
Also note that y=f(x) they are the same thing you can use y and f(x) interchangeably

Answer 6

@justsmile531

Answer 7

Its A

Answer 8

equate the function shipping cost as a function of weight + packing
y = m x + b
total cost = cost per pound * weight + packing fee
cost per pound = change in cost/ change in weight
slope of line = change in y/ change in x