How do you find the dimensions of the rectangle of greatest area whose perimeter is 20 cm?
1 Answer
Feb 7, 2017
Explanation:
Let the length of one side of the rectangle be
Then the opposite side is also of length
#(20-2x)/2 = 10-x# #"cm"#
The area of the rectangle is:
#x(10-x) = 10x-x^2 = 25-25+10x-x^2 = 25-(x-5)^2# #"cm"^2#
This attains its maximum,
Hence the rectangle of maximum area is a