This question is unsolvable this might be a trick question but it is not solvable. Hope this helps! ;D
Without seeing the graph, it's impossible to tell. The same can be said if we don't know the function rule. However, we can rule out three non-answers.
Choice B is false because the interval [1,3] has f(x) below zero but the rest of the interval to the right of x = 3 has f(x) not below zero.
Choice C is false. The value x = -1 leads to f(x) = 0 which is not greater than 0
Choice D is false because the values 8 and 4 are positive
After eliminating B, C, & D, we are left with choice A as the answer.
Problema Solution
You have 800 feet of fencing and you want to make two fenced in enclosures by splitting one enclosure in half. What are the largest dimensions of this enclosure that you could build?
Answer provided by our tutors
Make a drawing and denote:
x = half of the length of the enclosure
2x = the length of the enclosure
y = the width of the enclosure
P = 800 ft the perimeter
The perimeter of the two enclosures can be expressed P = 4x + 2y thus
4x + 3y = 800
Solving for y:
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click here to see all the equation solution steps
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y = 800/3 - 4x/3
The area of the two enclosure is A = 2xy.
Substituting y = 800/3 - 4x/3 in A = 2xy we get
A = 2x(800/3 - 4x/3)
A =1600x/3 - 8x^2/3
We need to find the x for which the parabolic function A = (- 8/3)x^2 + (1600/3)x has maximum:
x max = -b/2a, a = (-8/3), b = 1600/3
x max = (-1600/3)/(2*(-8/3))
x max = 100 ft
y = 800/3 - 4*100/3
y = 133.33 ft
2x = 2*100
2x = 200 ft
