2. If and are similar projects, then _ _ _ _ _ _ _.

Of all the letters in this sentence. The frequency of the letter ""is _ _ _ _ _.

4. In the equation, _ _ _ _ _ _ if it is expressed by an algebraic expression.

5. Fill in the two squares of equation 3×-2× = 15, so that the two numbers are opposite and the equation is established. Then the number in the first box is _ _ _ _ _ _ _.

6. The degree of the known complementary angle is _ _ _ _ _.

7. Given that the line segment AB=2cm, extend AB to point C, so that BC=4cm, and D is the midpoint of AB, then the line segment DC = _ _ _ _ _ _

8. As shown in the picture, a pair of triangular plates are placed on the desktop (the right-angled vertices coincide). If ∠ AOD = 145, ∠ BOC = _ _ _ _ _

Question 8 Question 9 Question 10

9. As shown in the figure, a school organized students to carry out "eight honors and eight disgraces" publicity and education activities, and some students walked out of the school gate to give lectures. This part of the students should be _ _ _ _ _ _ _ _ in the fan chart. (Choose, and then fill in the blanks)

10. As shown in the figure, observe the triangular array of numbers. According to this rule, the first number in line 8 is _ _ _ _ _ _ _ _.

1 1. The owner of a store first raises the price of a commodity whose purchase price is 800 yuan, and then sells it at a 20% discount, so the profit from selling this commodity is RMB.

12. Give the following procedures:

If the input value is 1, the output value is1; If the input value is-1, the output value is-3; Then when the input value is, the output value is _ _ _ _ _ _ _.

Second, multiple-choice questions (this big topic ***9 small questions, 2 points for each small question, *** 18 points)

13 14 15 16 17 18 19 20 2 1

13. In the construction of the "Bird's Nest" steel structure of the National Stadium of the "2008 Beijing" Olympic Games, the steel with strength of Pa independently developed by Chinese researchers was used for the first time, so the original number was ().

a . 4 600 000 b . 46 000 000 c . 460 000 000d . 4 600 000 000

14. If is, the value of is ().

In 2007

15. As shown in the figure, the straight line AB and CD intersect at point O, ∠ AOD+∠ BOC = 236, then ∠AOC= ().

A. 144 B. 124 C.72 D.62

16. The ancient "river map" in China consists of 3×3 squares, each square has different numbers of dot maps, and the sum of the points of the three dot maps on each row, column and diagonal is equal. As shown in the figure, some dot diagrams of "river map" are given. Please calculate that the point map corresponding to point P is ().

17. As shown in the figure, the view of a geometric figure composed of six cubes with the same size is correct ().

A. the front view has the largest area. B. The left view has the largest area.

C. the top view has the largest area. D. the three views have the same area.

18. If the solution of the equations is, then the solution of the equations is ().

A.B. C. D。

19. As shown in figure, AB‖DE, the following statement must be correct ().

A.B. C. D。

Question 19, question 2 1

20. On the same plane, there are eight non-overlapping straight lines. If,,, ... and so on, the positional relationship between and is ().

A. parallel B. vertical C. parallel or vertical D. uncertain

2 1. Xiao Li bought several kilograms of watermelons from the wholesale market at the price of RMB per kilogram and took them to the market for sale. After selling some watermelons, the rest were sold out at a reduced price of RMB per kilogram. The relationship between the sales amount and the kilograms of melons sold is shown in the figure, so Xiao Li earned ().

A.32 yuan B. 36 yuan C. 38 yuan D. 44 yuan

Third, answer the question (this topic is entitled *** 10, with a score of ***56, and the necessary steps in the answer process need to be written)

22. (6 points for this question) Calculation:

( 1) (2)

23. (8 points for this question) Solve the equation:

( 1) (2)

24. (8 points for this question) Solve the equation:

( 1) (2)

25. (4 points for this question) Simplify first, then evaluate:, in which

26. (5 points in this question) If it is known that the complementary angle of an angle is equal to the complementary angle of this angle, try to find the degree of this angle.

27. (5 points in this question) In order to improve the service quality of the bank, the time spent by 30 customers at the window (unit: minutes) was randomly selected. The figure below is the statistical chart obtained from this survey. Please answer the following questions according to the information in the picture:

(1) The number of people who spend 1 1 minute on handling business is:

(2) completing the bar graph;

(3) Try to find the average time for these 30 customers to handle business.

28. (5 points in this question) As shown in the figure, it is known that AD⊥BC is in D, EG⊥BC is in G, and E = ∠1. Verification: AD divides equally ∠ BAC.

The following is part of the reasoning process, please complete it:

∵AD⊥BC in D, EG⊥BC in G (known)

∴∠ADC=∠EGC=90

∴AD‖EG()

∴∠ 1=∠2( )

=∠3 (two straight lines are parallel and have the same angle)

∫∠E =∠ 1 (known)

∴∠2=∠3( )

∴AD splitting ∠BAC ()

29. (5 points in this question) As shown in the figure, it is known that: AD⊥BC, EF⊥BC, ∠ 1 = ∠ 2. Verification: ∠ 3 = ∠ b.

30. (5 points for this question) The following figure shows the corresponding relationship between the set of equations and their solutions arranged according to certain laws. If the equations in the system of equations are recorded as equation 1, equation 2, equation 3, ... the equations are arranged from left to right.

(1) Fill the solution of the equation group 1 in the diagram;

(2) Please fill the equations and their solutions directly into the set diagram according to the changing law of the equations and their solutions;

(3) If the solution of the equations is the value of, judge whether the equations conform to the law in (2)?

3 1. (5 points in this question) A middle school will organize seventh-grade students to have a one-day spring outing. Teacher Wang and students A and B go to the bus rental company to discuss car rental.

(1) Two students asked the company manager the price of renting a car. The manager of the company said to them, "The company has 45 and 60 buses for rent, and the daily rent of 60 buses is more than 45 buses 100 yuan." Teacher Wang said, "Our school rented five 45-seat buses and two 60-seat buses from this company yesterday. The daily rent is. Two students, A and B, thought for a moment and said they knew the price.

Clever, do you know the daily rent of 45-seat and 60-seat buses?

(2) The company manager asked, "How are you going to rent a car?" A classmate said, "My plan is to rent only 45-seat buses, but there will be 30 seats left in one car"; Classmate B said: "My plan only rents 60 buses, which is just full, using two fewer buses than classmate A's plan." Teacher Wang listened to their conversation and said, "From an economic point of view, is there any other plan?"

If it is you, how should you design a car rental scheme and explain the reasons?

Reference answer of junior one mathematics

Fill in the blanks

1., 2.；

3.4.

5.6.

7.8.

9. 10.

1 1. 12.

Second, multiple choice questions

13 14 15 16 17 18 19 20 2 1

C C D C C C B A B

Third, answer questions.

22.( 1) ; (2) ;

23.( 1) ; (2) ;

24.( 1) ; (2) ;

25. The original formula is =, and the value is;

26.；

27.( 1) ; (2) ellipsis; (3) minutes;

28. Omission;

29. Omission;

30.( 1) ; (2) ; ; (3) It does not comply with Article (2) of the law;

3 1.( 1)45 passenger cars are rented in 200 yuan and 60 passenger cars are rented in 300 yuan; (2) It is economical to rent 4 buses with 45 seats and 60 buses 1 vehicle at a cost of 1 100 yuan. First, can you fill it out quickly and accurately? (20×2 points = 40 points)

1. If 5m moving eastward is marked as +5m, 3m moving westward should be marked as m. ..

2. The number that is neither positive nor negative is.

3. The inverse of-(-3) is; The reciprocal of 1 is.

4. If a < 0, |a|=.

5. The coefficient of single item-is, and the number is.

6. If | A+3 |+(b-2) 2 = 0, then A-B =.

7. as shown in figure 1: ab.

The complementary angle of 8.69 30' is equal to.

9.0.02079 Keep three significant figures.

10. The sum of monomial -x2my and x6yn is monomial, then m =, n =.

1 1. Polynomials a4+4a3b-6ab2+4ab3 are arranged in descending order of B as follows.

12. Nail a piece of wood to the wall, at least, according to.

13. Write 15800000 according to scientific notation.

14. As shown in Figure 2: ∠ 1 = ∠ 2, then ∠, ∠ bad+= 180.

Second, you can definitely choose the right one! (3 points ×8 = 24 points)

15. Regarding rational numbers, the following statement is true ().

(a) the largest number; (b) has the smallest absolute quantity.

(c) The minimum number; (d) Has the largest absolute quantity.

16. It is known that A, B and C are rational numbers, so the inverse of a+b+c is ().

(A)b+ A-C(B)-B- A-C(C)-B- A+C(D)B- A+C

17. There are any three points on the plane, after which the number of straight lines can be drawn ()

(A) 1 (B) 3 (C) 1 or 3 (D) countless.

18.A and b are reciprocal, and x and y are reciprocal, so the value of (A+B) (X+Y)-AB is ().

(a) 0 (b) 1 (c)- 1 (d) cannot be determined.

19. Among the following groups, the group that correctly judges the size relationship is ().

(A)(-2)3>-23 (B)(-2)2< 22)

(C) - >- (D)(-2)3>(-2)2

20. If the single digit of a two-digit number is A and the ten-digit number is B, then this two-digit number can be expressed as ().

(A)A+B(B)ba(C) 10b+A(D) 10a+B

2 1. The cube shown in the figure, if expanded, can be () in the figure below.

(A) (B) (C) (D)

22. In the drawing, ∠ 1 and ∠2 are at the same angle ().

(A)①、② (B)①、③ (C)②、③ (D)②、④

① ② ③ ④

Third, do the math! Do not make mistakes! ! !

23. Calculation: (3 points for each question, *** 12 points)

( 1) (2)- 14+50÷22×(― )

(3) (4)0÷(-5)- 53- 5

Fourth, know the map calculation: be sure to look! ! ! (3 points for each question, ***6 points)

24. As shown in the figure, given that the line segment AB = 10㎝, and C is the midpoint of AB, find the length of AC;

25. As shown in the figure, it is known that: AD//BC, 1 = C, B = 60o, and the degree of c is found;

Verb (abbreviation of verb) explanation: (***4 points)

26. It is known that B, A and E are in a straight line, 1 = B Q: Is C equal to 2? Why?

Sixth, inquiry questions: have a look, don't be confused! ! ! (4 points for 27 questions, 5 points for 28 and 29 questions, *** 14 points)

27. Observe the graph and answer the question: What are the conditions for doing AD//BC?

(Requirements: Find at least 5 conditions)

Answer: ① ②

③ ④

⑤

28. There is a question: "Calculate (2x-3x y-2xy )-(x-2xy+y )+(- x).

+3x y-y), where x =, y =- 1. "A classmate copied" x = "by mistake.

"x =-", but his calculation result is also correct. Try to explain why? And find this result?

29. The total length of the Great Wall in Wan Li is one kilometer, and the length of a brick is b meters. How many bricks does Qin Shihuang need to repair the first floor of the Great Wall? If the total length of the Great Wall is 4,500 kilometers and the brick length is 15 cm, how many bricks does a floor need?

Or you can go to a learning network-Rubik's Cube, where there are many problems. )

Ok, please choose. Thank you.