A) multiple the 3 x 4 and add 1.
3 x 4 = 12 + 1 = 13
13/3
B) (7 x 3) + 2 = 23/3
C) (4 x 2) + 1 = 9/2
D) (2 x 8) + 7 = 23/8
Step-by-step explanation:
-18.4,-17.3,-1.4,7.8,15.8,16.2
Answer:
90 engines must be made to minimize the unit cost.
Step-by-step explanation:
Vertex of a quadratic function:
Suppose we have a quadratic function in the following format:

It's vertex is the point 
In which


Where

If a>0, the minimum value of the function will happen for 
C(x)=x²-180x+20,482
This means that 
How many engines must be made to minimize the unit cost?
x value of the vertex. So

90 engines must be made to minimize the unit cost.