Find the dimensions of a rectangle with perimeter 76 m whose area is as large as possible. m (smaller value) m (larger value)

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Answer:

19 m

Step-by-step explanation:

Perimeter = 2(length + width) ; P = 2(l+w) - - (1)

Area = Length * width ; A = l*w - - - (2)

76 = 2(l+w)

76/2 = l+w

l+w = 38

l = 38 - w

Put l = 38 - w in (1)

A = (38-w)*w

A = 38w - w²

At maximum point:

dA/dw = 0

dA/dw = 38 - 2w

38 - 2w = 0

38 = 2w

w = 38/2

w = 19