SOLUTION: The function y = 3.50x + 2 represents the total amount of money, y, saved over x weeks. What is true about the function? A It is linear because it is always increasing. B It is

Algebra ->  Statistics  -> Scatterplots-graphs -> SOLUTION: The function y = 3.50x + 2 represents the total amount of money, y, saved over x weeks. What is true about the function? A It is linear because it is always increasing. B It is      Log On


   

Question 1005651: The function y = 3.50x + 2 represents the total amount of money, y,
saved over x weeks.
What is true about the function?
A It is linear because it is always increasing.
B It is linear because it increases at a constant rate.
C It is nonlinear because it is always increasing.
D It is nonlinear because it increases at a constant rate.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
it is linear because it has a constant difference each time.

the difference can be positive or negative, but it will be constant.

they are referring to this constant difference when they say it is increasing at a constant rate.

selection B is the correct choice.

the function is:

y = 3.50 * x + 2
when x = 0, y = 0*3.50 + 2 = 2
when x = 1, y = 1*3.50 + 2 = 5.50
when x = 2, y = 2*3.50 + 2 = 9.00
when x = 3, y = 3*3.50 + 2 = 12.50

every time x increases by 1, y increases by 3.50.

3.50 is the constant rate of increase in this problem.

graphing of a linear function results in a straight line.

the graph of this function is shown below:

graph%28600%2C600%2C-5%2C5%2C-15%2C15%2C3.5x%2B2%29

here's a good refernece on linear versus non-linear functions.

http://www.charleston.k12.il.us/cms/Teachers/math/PreAlgebra/paunit3/L3-3.PDF