Yes,y=2x+7 is a function
because x is argument,and it has x and y,it is a primary function
Answer:

Step-by-step explanation:
In this problem, we have that the cost of renting a car C is a function of the number of days d, and the number of miles driven, m.
There is also a fixed cost F.
So the equation for the cost of renting a car is:

In which a is the daily cost and b is the cost per mile.
A car rental company charges a one-time application fee of 20 dollars, 45 dollars per day, and 15 cents per mile for its cars.
This means that 
Write a formula for the cost, C, of renting a car as a function of the number of days, d, and the number of miles driven, m.

Answer:
The first one
Step-by-step explanation:
when you are doing work with decimals the less numbers behind the decimal the bigger the decimal the more numbers the smaller the decimal based on that, 3550 is the biggest so that would go first. 13 is the next biggest and 0.3 is the same as 0.30 and there are less numbers after the decimal so that is the next biggest. 0.35 would go next because there are more numbers behind the decimal which makes it the smallest. I hope this helps :P
Solution:
we are given that

we have been asked to find f(x).
we can find the value of f(x) by re-writing the given function in the form of f(x+3) and thereafter we will replace (x+3) by x.
we can re-write the given function as below

Hence the expression representing f(x) is f(x)=4x+3.