Question

PLEASE HELP!!! Pr-Cal Question 20 points

Answer 1

Answer:

3600

Step-by-step explanation:

perimeter is  120ft

Goal is to get the largest area.

so you can start with a list of possible solutions:

1*119 = 119ft

2*118 = 236ft

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60*60 =3600ft

61*59 = 3599ft

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Answer 2

Answer: it is well known that the largest area would be a circle with circumference 120 ft, and it is well known that a square 30ft on a side gives the most area of all retangles with perimeter 120 ft, but we are to prove it. The equation is area = side × (60 - side).

Step-by-step explanation:

Let s be one side of the rectangle, and 60-s be the other side. Maximize the area, which is

a(s) = s×(60-s) = -s^2 + 60s

This quadratic equation reaches a maximum when da(s)/ds = 60 - 2s = 0.

2s = 60, s = 30.