For this case we have a function of the form 
Where:

We must find the value of the function when x = 3. Then we substitute:

Thus, the value of the function when
is 
Answer:

Option C
I would say this 7 because when you subtract
The queen size mattress has a catalog price of 428.99 dollars.
NOw, it has a trade discount rate or 20%
=> 20% / 100% = .20
Next is to do the solution:
=> 428.99 * .20 = 85.798 dollars or 85.80
Now, let's find out the net price:
=> 428.99 - 85.80 = 343.19 dollars or 343.2.
Answer;
X = 18: AD = 18
Step-by-step explanation:
Here, we want to find the measure of AD
From the given image;
AB = x + 3
AD = x
AC = 24 + 4 = 28
AE = 24
Substituting these values
we have ;
(x + 3)/x = 28/24
24(x + 3) = 28x
24x + 72 = 28x
28x - 24x = 72
4x = 72
x = 72/4
x =18
I believe the answer is a