The answer is: "12 feet" .
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Note: In a square, the length of EACH of the four sides of the square is the same.
Area = Length * width.
For a square, length = width.
So for a square, Area = length * width = (length of a side)² = s² ,
Given: A = s² = 144 ft² ;
Solve for the positive value of "s" .
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→ s² = 144 ft² ; Take the "square root" of each side ;
→ √(s²) = √(144 ft²) ;
→ s = 12 ft.
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The answer is: 12 ft.
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Answer:

Step-by-step explanation:




Answer:
get stuff out of parentheses solve obvious problems, solve x
if there is figure add figure
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.