As shown in the figure, a trapezoidal Street garden is divided into two parts: parallelogram and triangle. Peony and rose are planted respectively. Peony covers an area of 300 square meters, and rose covers an area of how many square meters?

As shown in the figure, a trapezoidal Street garden is divided into two parts: parallelogram and triangle. Peony and rose are planted respectively. Peony covers an area of 300 square meters, and rose covers an area of how many square meters?

A: Rose covers an area of 150 square meters

The park has an equilateral triangle with a side length of 2, which is now lawn
There is a point E on the AC side of triangle ABC and a point D on the AB side. De divides the lawn into two parts with equal area. (1) let ad = x (x is greater than or equal to 0), ed = y, and find the functional relation of Y expressed by X
(2) What is the location of the maximum and minimum of de?

(1) In △ ade, y2 = x2 + ae2-2x · AE · cos, 60 ° y2 = x2 + ae2-x · AE, 1
And s △ ade = s △ ABC = A2 = x · AE · sin60 ° x · AE = 2. ②
② Y 2 = x 2 + - 2 (Y > 0), y = (1 ≤ x ≤ 2)
(2) If De is water pipe, y = ≥,
If and only if x 2 =, i.e. x = then "=" holds, so de ‖ BC, and de =
If De is a tour route, f (x) = x2 +
The function decreases on [1,] and increases on [, 2],
So f (x) max = f (1) = f (2) = 5
When De is ab or AC, De is the longest

For a lawn with a length of 16 meters and a width of 9 meters, a stone road with a width of 1 meter should be paved around the lawn. It takes 60 kg of stones per square meter. How many kg of stones do you need to pave this road

(16 + 1 + 1) * (9 + 1 + 1) = 198 (M2)
198-16 * 9 = 54 (M2)
54 * 60 = 3240 (kg)