In the figure, ABCD is a rectangle. E is the mid-point of BC. F is a point lying on CD such that DF = 3CF. If the area of triangleABE is 2 cm2, then the area of triangleAEF is
In the figure, the coordinates of A are (1, -1). L is a horizontal line passing through (0, 2). A is first translated to the left by 4 units to B, and then reflected about L to C. Find the coordinates of C.
In Figure 1, the side length of the cubic tank is 15 cm. The depth of the water in the cubic tank is 5 cm. If 3 identical metal balls are put into the tank, the depth of the water in the tank will become 7 cm (see Figure 2). Find the volume of each metal ball.
- 5 年前最愛解答
Let DF be 3X, then CF=X
Area of ABE = 4xy/2 = 2 --> xy=1
Area of ADF = (3x)(2y)/2 = 3xy = 3(1) = 3
Area of CEF = xy/2 = 1/2
Area of rectangle = (4x)(2y) = 8xy = 8
The required area = 8-3-2-1/2= 5/2
(2) Coordinates of B = (1-4, -1) = (-3, -1)
Coordinates of C = (-3, 2+3) = (-3, 5)
(3)Volume of the metal balls = 15 x 15 x (7-5) = 450
The required volume = 450/3 = 150
ANS: A資料來源： Ben Sir!!!