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There is a fence with a length of 24 meters and a wall (the maximum usable length of the wall is 9 meters) is used to form a rectangular flower bed with a fence in the middle. The width ab of the flower bed is x meters and the area is s square meters 1) Find the functional relationship between S and X and the value range of the independent variable x; 2) Find the maximum value of S and what is the value of X at this time?
Width = x
Length = 24-3x
03X≥15
5≤X
As shown in the picture, there is a fence with a length of 24 meters, and one side uses a wall (the maximum available length of the wall a is 13 meters) to form a rectangular flower garden with a fence in the middle
2x+y=24,y=24-2x
S = xy = x (24-2x) = - 2x square + 24x = - 2 (X-6) square + 72
So when x = 6, Smax = 72
As shown in the picture, there is a fence with a length of 24 meters. One side of the fence (the maximum usable length of the wall is 11 meters) is used to form a rectangular flower garden with a fence in the middle. (1) if a flower garden with an area of 45 square meters is to be enclosed, how long is ad? (2) Can a 60 square meter garden be enclosed? If you can, ask for the length of AD; if not, please explain the reason
(1) Let the length of ad be x meters, then AB be (24-3x) meters. According to the equation, we can get (24-3x) · x = 45, and the solution is X1 = 3, X2 = 5. When x = 3, ab = 24-3x = 24-9 = 15 ＞ 11, which does not conform to the meaning of the problem. When x = 5, ab = 24-3x = 9 ＜ 11, which conforms to the meaning of the problem
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