Answer:
$9327
Step-by-step explanation:
Apparently, the cost function is supposed to be ...
C(x) = 0.4x^2 -112x +17167
This can be rewritten to vertex form as ...
C(x) = 0.4(x^2 -280) +17167
C(x) = 0.4(x -140)^2 +17167 -0.4(19600)
C(x) = 0.4(x -140)^2 +9327
The vertex of the cost function is ...
(x, C(x)) = (140, 9327)
The minimum unit cost is $9327.
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<em>Comment on the question</em>
You found the number of units that result in minimum cost (140 units), but you have to evaluate C(140) to find the minimum unit cost.
Answer: 
Step-by-step explanation:
Move all terms to one side
Simplify 
Split the second term
Factor out common terms in the first two terms, then in the last two terms.
Factor out the common term 
Answer:
Step-by-step explanation:
step 1
Find the measure of the arc DC
we know that
The inscribed angle measures half of the arc comprising
![m\angle DBC=\frac{1}{2}[arc\ DC]](https://tex.z-dn.net/?f=m%5Cangle%20DBC%3D%5Cfrac%7B1%7D%7B2%7D%5Barc%5C%20DC%5D)
substitute the values
![60\°=\frac{1}{2}[arc\ DC]](https://tex.z-dn.net/?f=60%5C%C2%B0%3D%5Cfrac%7B1%7D%7B2%7D%5Barc%5C%20DC%5D)
step 2
Find the measure of arc BC
we know that
----> because the diameter BD divide the circle into two equal parts
step 3
Find the measure of angle BDC
we know that
The inscribed angle measures half of the arc comprising
![m\angle BDC=\frac{1}{2}[arc\ BC]](https://tex.z-dn.net/?f=m%5Cangle%20BDC%3D%5Cfrac%7B1%7D%7B2%7D%5Barc%5C%20BC%5D)
substitute the values
![m\angle BDC=\frac{1}{2}[60\°]](https://tex.z-dn.net/?f=m%5Cangle%20BDC%3D%5Cfrac%7B1%7D%7B2%7D%5B60%5C%C2%B0%5D)
therefore
The triangle DBC is a right triangle ---> 60°-30°-90°
step 4
Find the measure of BC
we know that
In the right triangle DBC
substitute the values
100,000,000
3.000.000
700,000
20,000
7,000
400
90
5
First let's find out how many cups serve one person.
3 ÷ 5 = 1.6
1.6 of a cup serves one person.
1.6 × 13 = 20.8
It takes 20.8 (21 rounded) to serve 13 people.
