He has to wait 13 minutes for the 7:18 train
Here is our profit as a function of # of posters
p(x) =-10x² + 200x - 250
Here is our price per poster, as a function of the # of posters:
pr(x) = 20 - x
Since we want to find the optimum price and # of posters, let's plug our price function into our profit function, to find the optimum x, and then use that to find the optimum price:
p(x) = -10 (20-x)² + 200 (20 - x) - 250
p(x) = -10 (400 -40x + x²) + 4000 - 200x - 250
Take a look at our profit function. It is a normal trinomial square, with a negative sign on the squared term. This means the curve is a downward facing parabola, so our profit maximum will be the top of the curve.
By taking the derivative, we can find where p'(x) = 0 (where the slope of p(x) equals 0), to see where the top of profit function is.
p(x) = -4000 +400x -10x² + 4000 -200x -250
p'(x) = 400 - 20x -200
0 = 200 - 20x
20x = 200
x = 10
p'(x) = 0 at x=10. This is the peak of our profit function. To find the price per poster, plug x=10 into our price function:
price = 20 - x
price = 10
Now plug x=10 into our original profit function in order to find our maximum profit:
<span>p(x)= -10x^2 +200x -250
p(x) = -10 (10)</span>² +200 (10) - 250
<span>p(x) = -1000 + 2000 - 250
p(x) = 750
Correct answer is C)</span>
Answer:
Let X be 2
Now,
y = 5*2 - 8
or, y= 10-8
or, y =2
Hope this will help please mark me as <em>brainlest.</em>

- How do you simplify this?
- x²y+xy² / y²+2/5 × xy


Factor the expressions that are not already factored.
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<u>How </u><u>to</u><u> factorise</u><u> </u><u>:</u><u>-</u>
<u>NUMERATOR</u> 

Factor out xy.

<u>DENOMINATOR</u> 

Factor out 1/5.

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Continuing...

Cancel out y in both the numerator and denominator.

Expand the expression.

This can further simplified to as 
