Carly is ordering calendars online. Each calendar costs $12, with a one-time shipping fee of $15. Which equation can be used to find the total cost, t, of ordering n calendars?

The answer is t=12n+15

Step-by-step explanation:

Step one:

Given data

Each calendar costs $12

Shipping fee = $15

let the number of calendars ordered be n

and let the total cost be t

Step two:

Required

The expression for the total cost t

t= 12n+15

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below: