The degree of 1. polynomial 3x2y+2y- 1 is ().
A, 1 time b, 2 times c, 3 times d, 4 times
2. The volume of a square with side length a is a3. If the side length is doubled, the volume is ().
a、2a3 B、8a3 C、 16 a3 D、a3
3. According to the data of the fifth national census in 2000, the total population of China is1295,330,000, with an accuracy of ().
a、 1.30× 109 B、 1.259× 109 C、 1.29× 109 D、 1.3× 109
4. The following four groups of numbers are the lengths of three sticks, and the one that can't be spelled into a triangle with them is ().
a、3cm、4cm、5cm B、 12cm、 12cm、 1cm C、 13cm、 12cm、20cm D、8cm、7cm、 16cm
5. It is known that the degrees of the three internal angles of △ABC are A, 2a and 3a respectively. This triangle is () triangle.
A, acute triangle B, right triangle C, obtuse triangle D, uncertainty
6. The national flag is the symbol of a country, and the national flags of the following four countries are not axisymmetric ()
A, Vietnam b, Australia
C, Canada d, Cambodia
7. Which of the following pictures can roughly reflect the speed change of sprinters from the starting point to the end point in the competition ()
A, B, C, D,
8. As shown in the figure, △ Abd△ CBE is known, and the following conclusion is incorrect ().
a、∠CBE=∠ABD B、BE=BD C、∠CEB=∠BDE D、AE=ED
9. Fold a rectangular piece of paper in half, then fold it in half and tear off a corner of the rectangle. The opened graph must have a () axis of symmetry.
A, a b, two c, three d and four.
10. There are two kinds of floors in the room, of which the area of the black floor is half that of the white floor, and there is a treasure hidden under the floor. The probability of hiding under the white floor is ()
a、 1 B、C、D、
I will fill it out. (3 points for each small question, *** 15 points)
1 1.22+22+22+22=____________。
12. When two sides of a triangle are 5cm and 8cm respectively, the range of the length of the third side is _ _ _ _ _.
13. The height of a triangle is x, the length of its base is 3, and the relationship between the triangle area s and the height x is _ _ _ _ _ _ _ _ _ _.
14. As shown in the figure, O is the midpoint between AB and CD, so the reason for △ OAC △ OBD is _ _ _ _ _ _ _.
15. There are two red balls, three white balls and five black balls in the schoolbag. Choose a ball from them, and the probability of touching the red ball is _ _ _ _ _.
Three. Problem solving (6 points for each small question, ***24 points)
16.(2mn+ 1)(2mn- 1)-(2m2n 2+2)
17. There is a question "Calculate the value of (2x3-3x2y-2xy2)-(x3-2xy2+y2)+(-x3-3x2y-y2), where x =, y =- 1." A classmate mistakenly copied X = as X =-, but his calculation result is also correct. What do you think is going on?
18. As shown in the figure, AB‖CD and straight line EF intersect AB and CD at points E and F, respectively. EG bisects ∠BEF and intersects CD at point G, ∠ EFG = 500, so find the number of times ∠BEG.
19. Kobayashi accidentally broke a triangular glass (as shown in the figure) on the door of the decorative cabinet while helping grandma clean. Kobayashi decided to use his pocket money to buy a glass of the same size in a glass shop for his father to install.
(1) Please use a ruler to help Xiao Lin draw a figure identical to the original triangle in the box below. (Don't write, leave traces of painting)
(2) Kobayashi found the glass shop with the drawings. The salesgirl measured it, and the three sides of the triangle were 20cm,15cm and 25cm respectively. The salesman said that the glass was sold by the square. Please help Xiao Lin estimate how many square meters it takes to buy a piece of glass of the same size.
4. Answer the questions. (7 points for each small question, ***2 1 point)
20. The picture below shows several 4×4 squares. Please draw four different divisions along the grid line and divide it into two congruent figures.
2 1. As shown in the figure, AB‖CD, AE = CF, ED‖BF, what do you think of △ ABF △ CDE in the figure? Please provide a justification for the answer.
22. Note that this short question provides two optional questions. Please answer any of the following 22- 1 and 22-2 questions, and do one more question without scoring.
22- 1. This painting is part of the butterfly pattern. Please draw another part of the pattern to make it take L as the symmetry axis. At this time, you will get a complete pattern of a beautiful butterfly. Give it a try. (non-writing method)
22-2. The picture below shows the time displayed by the electronic clock in the mirror. When do you think the actual time should be? Draw it in the back.
5. Answer the questions. (Each small question 10, ***30)
23. The following table is a statistical table of population density in China (population density is the population per square kilometer). Please draw a statistical map, as vivid as possible. And tell me what information you can get from the picture.
year
1949
1959
1969
1979
1989
1999
2003
population density
57
70
84
102
1 18
13 1
134
24. Analyze the relationship between variables reflected in the figure below, imagine an actual situation suitable for it, and write it out for everyone to share.
25. Choose one of the following two questions to answer.
25- 1. Xiao Ke plays games with Xiao Ai. Xiaoke has a group of cartoons, one is Mickey Mouse, and the other two are Snoopy. Let Xiao Ai draw two pictures from among them. If Mickey Mouse and Snoopy are taken away, Xiao Ai loses and Xiao Ke wins. Is the game fair? What are the chances of Xiao Ai winning?
25-2. Both China Sports Lottery and China Welfare Lottery have 3D gameplay, and the gameplay is a note by 2 yuan. If the selected three digits are the same as those drawn in the lucky draw, you will get a bonus of 1 1,000 yuan. Would you please explain the winning probability of this game with your knowledge? How many bets do I have to buy to win the prize? How to buy?
Reference answer: (There is no unique answer to the question about drawing in this answer, and this answer is for reference only)
1. Multiple choice question: CBADB BADBD
2. I will fill in:11.1612. More than 3 and less than 13 13. S = x 14。 A triangle with two equal angles is congruent.
3. Fill in the blanks:16.2mn2317. The original formula is simplified to -6x2y-2y2, and x2 is the same whether X is or-. 18.650
19.0.05438+05m2
IV.20. (The answer is not unique)
2 1.ED‖BF gets ∠ AFB = ∠ CED, AB‖CD gets ∠ A = ∠ C; Ae = cf plus EF on both sides can get af = ce. According to the corner theorem, two triangles can be congruent.
22.
( 1) (2)
V.23 (The answer is not unique)
As can be seen from the picture, the population of our country is increasing. Since 1999, population growth has been slow under the control of the state. (as long as it makes sense)
24. (The answer is not unique) Xiaoming went to school. After walking for a while, he saw an acquaintance and chatted with him for a while. He found that he was going to be late. After saying goodbye to his acquaintances, he hurried to school.
25.( 1) The game is unfair, and the probability that Xiao Ai will win is.
(2) The probability of winning the 2)3D grand prize is that if you want to win the grand prize, you must buy at least 1000, from 00 1 to 999.
Hope to adopt, O(∩_∩)O Thank you.