The answer is 18 I’m pretty certain so D
Answer:
The smallest value of p+q is 11
It happens when p = 6 and q = 5.
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Explanation:
Let's factor 180 in such a way that exactly one factor is a perfect square.
I'll ignore the trivial factor of 1.
Here are the possible factorizations we could go with:
180 = 4*45
180 = 9*20
180 = 36*5
Those factorizations then lead to the following

Then we have
p+q = 2+45 = 47
p+q = 3+20 = 23
p+q = 6+5 = 11
The smallest value of p+q is 11 and it happens when p = 6 and q = 5.
Side note: p+q is smallest when we go with the largest perfect square factor.
Answer:
The number of elephant ears that must be sold to maximize profit is 400.
Step-by-step explanation:
Given that,
The profit that a vendor makes per day is given by
P(x)= - 0.004x² +3.2 x -200
where x is number of elephant ears.
P(x)= - 0.004x² +3.2 x -200
Differentiating with respect to x
P'(x)= - 0.008x+3.2
Again differentiating with respect to x
P''(x) = -0.008
For maximum or minimum P'(x)=0
- 0.008x+3.2=0
⇒0.008x=3.2

⇒ x = 400

Since at x=400, P''(x)<0, the profit is maximize.
P(400) = -0.004×400²+3.2×400-200
=440
The number of elephant ears that must be sold to maximize profit is 400.
In an equation using x is just a place holder because those numbers are variables so it doesn't matter whether it is x or w.