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.