Answer:
We have to use the formule to calculate the vertex which is: V(-b/2a;4ac-b^2/4a)
A) y=x+7 where a=1 b=0 and c=7
By replacing we have: V(0;28/4) V(0;7)
B) y=-x where a=-1 b and c=0 so V(0,0)
 
        
             
        
        
        
Answer:
Part A: x0.50 + 3 = 18.50
Part B: x0.75 + 3 - x0.10 = 21
Part C: The equations from Part A and Part B differ because of the cost of plastic cup.
Step-by-step explanation:
Let x represent the number of cup of lemonade sold. Therefore, we have:
Part A: 
This situation can be represented by the following equation:
x0.50 + 3 = 18.50
Part B:
This situation can be represented by the following equation:
x0.75 + 3 - x0.10 = 21
Part C:
The equations from Part A and Part B differ because of the cost of plastic cup.
For equation from Part A, revenue is the same as profit as Sydney does incur any cost to buy plastic cup before selling her lemonade.
For equation from Part B, revenue is different from profit because Daria has to incur the cost of plastic cup which $0.10 per cup of lemonade before selling her lemonade.
 
        
                    
             
        
        
        
Answer:43?
Step-by-step explanation:
 
        
             
        
        
        
Answer:
B- Line Q
Step-by-step explanation:
Line Q is practically in the middle of the dots. It is called a trend line btw. :)
 
        
                    
             
        
        
        
Answer:
This is just a relation.
Step-by-step explanation:
It is easy to see if a set of ordered pairs is a relation or a relation that is a function.
If all the points are distinct, then you just have to look at the  -coordinates.
-coordinates.
If all the  -coordinates are different, then it is a function. Otherwise, it is a just a relation.
-coordinates are different, then it is a function. Otherwise, it is a just a relation.
So this cannot be a function because there is at least two different points that have  .
.