Question
David has 200m of fencing to enclose three identicle rectangular pens as shown in the figure. Let x be the length of each pen.
a) express the total area of the pens in terms of x
My answer: 2x^2-100x
(It is correct according to the answer key)
b) find the maximum total area of the pens
????????
Thankyou!!
a) express the total area of the pens in terms of x
My answer: 2x^2-100x
(It is correct according to the answer key)
b) find the maximum total area of the pens
????????
Thankyou!!
Answers
Steve
the maximum area is at the vertex of the parabola.
That is always at the axis of symmetry, x = -b/2a
In this case, that is at x = 100/4 = 25
2*25^2 - 100*25 = -1250
???
Your function cannot be correct, since it is a parabola opening upward, and thus has no maximum. The coefficient of x^2 must be negative for the function to have a maximum.
That is always at the axis of symmetry, x = -b/2a
In this case, that is at x = 100/4 = 25
2*25^2 - 100*25 = -1250
???
Your function cannot be correct, since it is a parabola opening upward, and thus has no maximum. The coefficient of x^2 must be negative for the function to have a maximum.