The answer to this would be x-(x+14)
Here's an explanation:
Let x represent the unknown number. The problem says that x has been decreased by the sum of x and 14. So, to put this in a form of an equation, it would be x-(x+14), since you have to do the addition first before you can subtract the two number since you don't know what x is. This equation is equal to -14 no matter what x is. 
 
        
             
        
        
        
Answer:
The number of tickets for sale at $26 should be 3300
The number of tickets for sale at $40 should be 1700
Step-by-step explanation:
Use 2 equations to represent the modifiers within the problem:

Now you want to find the point at which the variables are changed to make both equations correct, this can be done by graphing and finding the intersection of both lines.

 
        
             
        
        
        
I’m not sure what the first one is, but number 4 is A) y=2x+4
        
                    
             
        
        
        
Answer:
x=18
Step-by-step explanation:
So (3x+20)° and (5x-16)° are angles that are vertically opposite to each other; which means that they are equal to one another. Which means we can say:
(3x+20)=(5x-16)
20+16=5x-3x
36=2x
x=18
*and the two angles are 74°