Test question 2:
1. Multiple choice questions (24 points, 3 points for each small question)
1. Which of the following is true?
A36= 6 B-3-8 =-2 C(-6)2=-6 D3-7=-37
The square root of 2. -3-64 Yes
A, 4 b, 2 C, 2 d, does not exist
3. As shown in the figure, it is known that △ABC, p is a point on AB and CP is connected. In the following conditions, △ACP∽△ABC cannot be determined.
A∠ACP=∠B B∠APC=∠B
ACAP = ABAC ACAB = CPBC
4. Simplifying 12x results in
a、2x3 B、2x3c、2x2x D、3x2x
5. Among the four points given below, the point not on the straight line Y = 2x-3 is
a 、( 1，- 1) B 、( 0，-3) C 、( 2， 1) D 、(- 1，5)
6. When the car starts driving, there is 40 liters of oil in the fuel tank, so the functional relationship between the remaining oil quantity Q (liter) in the fuel tank and the driving time T (hour) is ().
7. If the inverse proportional function y = 2m- 1x, and y decreases with the increase of x, the value range of m is
a、m & gt 12 B、m & lt 12 C、m & gt- 12 D、m & lt- 12
8. No matter M takes any nonzero real number, the image of linear function Y = MX-(3m+2) passes through the fixed point.
a 、( 3，2) B 、( 3，-2) C 、( 3，2) D 、( 3，-2)
Fill in the blanks (3 points for each small question ***36 points)
9.(-3)2=
10. If x= 15, then x=,
1 1. The arithmetic square root is equal to its own number.
12. If two triangles are similar, the similarity ratio is 5:8, and the corresponding height ratio is,
13. If the integer x satisfies the relation 3.
14. In real numbers 227, 8, 0.3, π 2, 9, 32 16, 1-3, the number of positive irrational numbers is.
15. If (x+ 1) 2+y-3 = 0, then x+2y=.
16. The value range of the independent variable x in the function y = 15-x is.
17. points A (a, -5) and (3, b) are symmetrical about x, then a=, b=.
18. Tea eggs are 0.55 yuan each. The functional relationship between the number of tea eggs X bought by Xiao Ming and his classmates and the amount of money Y (yuan) paid is, and the range of independent variable X is.
19. the linear function y = (2-k) x+2 (k is a constant), and y increases with the increase of x, then the range of k is.
20. As shown in the figure, EC‖AB, ED‖BC, there are three pairs in the figure.
Similar triangles, they are.
Thirdly, simplification and evaluation.
2 1. calculation (4 points for each small question *** 16 points)
⑴ 8-4- 18 ⑵ ( 1-23)2
⑶ 3 12-32+2 ⑷ 50+328
22. (4 points in this question) Find the value of x.27 (x-2) 3 = 8.
23. (8 points in this question) A farmer brought some kilograms of potatoes to the city to sell. He brought some pocket money for convenience. After selling some potatoes at the market price, he sold them at a reduced price. The relationship between the number of kilograms of potatoes sold and the amount of money (including spare money) in his hand is shown in the figure. Answer with pictures:
(1) How much change have farmers brought?
What was his price per kilogram of potatoes before the price reduction? List the functional relationship between the number of kilograms of potatoes sold before the price reduction and the amount of money he holds (including spare money)?
(3) After reducing the price, he sold out every kilogram of potatoes in 0.4 yuan. At this time, his money (including spare money) was 26 yuan, and he asked him how many potatoes he had brought to the city to sell.
24. (8 points in this question) As shown in the figure, it is a functional image of a cyclist and a motorcyclist driving from place A to place B along the same route. The distance between the two places is 80 kilometers. Please solve the following problems according to the pictures:
(1) L 1 is the function image of the driving process, and l2 is the function image of the driving process;
(2) Who started early? How early? Who arrived at the destination ahead of time? How early?
(3) Find out how fast two people drive on the road.
⑷ Calculate the resolution function representing the driving process of bicycle and motorcycle, and the range of independent variable X respectively. ..
25. (6 points in this question) As shown in the figure, in △ABC, if DE‖BC, AD = 3, AE = 2, BD = 4.
(1) Description △ADE∽△ABC
(2) Seek the value of AEAC.
(3) Calculate the length of AC and EC.
26. (8 points for this question) Read the following passage:
Figure 18.35 shows two similar cuboids, and their similarity ratio is 3∶5. Find their volume ratio.
Solution: What is the volume of a cuboid (A)? 3b？ 3c=33abc, and the volume of the cuboid (b) is 5a? 5b？ 5c=53abc, so the volume ratio of cuboid (a) to cuboid (b) is 33abc ∶ 53abc = 33 ∶ 53 = (3 ∶ 5) 3.
So the volume ratio of similar shapes is equal to the cube of its similarity ratio.
Please copy the example above to answer the following questions:
Fish is a high-protein food, so everyone wants to buy cheap fish. Suppose the same fish (similar in shape) is sold in the market now, and the prices of big fish A and small fish B are 1.5 yuan and 1 yuan per catty respectively. If the height of big fish is 13 cm, then the height of small fish is 10 cm (Figure 65438+).
27.( 10 point) As shown in the figure, in the rectangular ABCD, AB = 12cm, BC = 6cm, point E starts from point A and advances to point D at a speed of 1cm per second, while point F advances from point D to point C at a speed of 2cm per second. If the moving time is t, and 0≤t≤6
(1) When t is what, DE = 2DF；;
(2) Whether the area of the quadrilateral DEPF is a fixed value, and if so, request a fixed value; If it is not a fixed value, please explain the reason.
(3) Can a triangle with vertices d, e and f be similar to △BCD, and can all possible values of t be found? If not, please explain why.
I finally found it for you. I hope it will help your study!
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