1. The following statement about the monomial is true ()
A. the coefficient is 3, the degree is 2 b, and the coefficient is 2.
C. the coefficient is, the degree is 3 d, and the coefficient is-the degree is 3.
2. In the following events, the number of uncertain events is ()
(1) If x is rational, then
Dandan can walk 20 kilometers per hour.
(3) Choose one card from a deck of playing cards. This playing card is king.
④ Pick a ball from the pocket containing 9 red balls and 1 white balls. It is a red ball.
A. 1 B. 2 C. 3 D.4
There are still many space technology problems to be solved to send humans to Mars. For example, it is known that an adult breathes an average of 6.57× liters of oxygen every year, but at present it takes two years for a spaceship to fly to Mars. If there are three astronauts on board, theoretically, you need () grams of oxygen. (Oxygen is1.43g/L, the result is expressed by scientific notation, and three people are reserved.
A.B. C. D。
4. The intersection of straight lines with three heights of an obtuse triangle is in ()
A. inside the triangle B. outside the triangle C. on the side of the triangle D. uncertain
5. The following can't be calculated by the square difference formula is ()
A.B.
C.D.
6. In the western mountainous area, there is a student from Hope Middle School standing in front of the mirror, so the image of his school emblem in the mirror is ().
7. In the following calculation, Xiao Mahu only answered one question correctly. The topic he answered correctly was ().
A.B.
C.D.
8. If the bisector of ∠ABC and ∠ACB in △ ABC intersects at point I ∠ ABC+∠ ACB = 100, then the degree of ∠BIC is ().
A.80 B. 50 C. 100 D. 130
9. In the following four pictures, ∠ 1 and ∠2 have the same angle ().
① ② ③ ④
A.②③ B. ①②③ C. ①②④ D. ①
10. A candle is 20 cm long and burns 5 cm per hour after being lit. The relationship between the residual height h (cm) and the combustion time t (hours) is graphically represented as ().
Fill in the blanks (2 points for each small question, 20 points for * * *)
The 1. polynomial has a term () of degree ().
2. The following data is approximate (). (Fill in serial number)
There are 15 boys in Xiaohong's class:
② Mount Everest is 8844.43 meters above sea level.
According to the population report released by the United Nations on February 27th, 20001,it is estimated that15.5 million people in the world will die of AIDS in the next five years, but now it seems that there are more than this number.
④ Lingling's height is1.60m. ..
3. Observe the plan below, in which the axisymmetric figure is (). (Fill in serial number)
4. The numbers 1, 2, 3, 4, 5, 6 are marked on six faces of a unified small cube. If you throw this small cube at will, the probability that the number is a multiple of 3 is ().
5. As shown in the figure, the radius of fan-shaped OAB is 10. When the degree of the central angle of the fan-shaped OAB changes, the area of the fan-shaped OAB changes. In the process of this change, the independent variable is () and the dependent variable is ().
6. The radius of a circle is r, the radius of another circle is five times that of this circle, and the sum of the perimeters of these two circles is ().
7. There are four line segments, the lengths of which are 2cm, 6cm, 8cm and 9cm respectively. Choose three of them to form a triangle. There are () ways to form a triangle.
8. As shown in the figure, the straight line AB intersects with CD at point O,OE⊥AB,OF⊥CD, if ∠EOF= ∠AOD,
Then ∠EOF= () degrees.
9. As shown in the figure, in △ABC, AD is the height on the side of BC, AE bisects ∠BAC, ∠ B = 70, ∠ C = 40, then
∠DAE= () degrees, ∠AEC= () degrees.
10. As shown in the figure, Xiao Ming built 1, 2, 3 "goldfish" with matches. According to this rule, you need matches () when you build the N "Goldfish". The first fish used eight matches.
Three. (7 points for each question, *** 14 points)
1. Calculation:
2. Simplify first, then evaluate:
, in which
Four. (Question 65438 is 6 points +0, question 2 is 8 points, *** 14 points)
1. As shown in the figure, in the L-shaped figure composed of small squares, please draw a small square in the figure below in three different ways to make it an axisymmetric figure.
2. As shown in the figure, it is the statistical table of port throughput planning of newly developed seaports in 2007-201KLOC-0/a city.
(1)(4 points) Look at the picture and briefly describe the characteristics of the five-year port planning: (Write only two points)
(2)(4 points) The development of the seaport will strongly promote the economic development of the city. If the throughput per 10,000 tons can bring 654.38+10,000 yuan to our city, then according to the plan, how many billion yuan will the seaport * * add to our city's finance in five years?
Five (7 points +0 for question 65438, 8 points for question 2, *** 15)
1. Xiaodong found a math textbook with a calendar. It is known that the teaching material is one centimeter long, two centimeters wide and three centimeters thick. Xiaodong wants to fold m cm on both sides of the book cover when wrapping the front cover and back cover of the textbook, and asks Xiaodong how big a rectangle should be cut on the calendar painting.
2. The picture below shows the income change of a factory in one year. According to the picture, this year:
①(4 points) When is the highest income? When is the lowest income? What are the highest income and the lowest income respectively?
(1) What was the profit in June?
(1) Which month's income is 4 million?
(4) (1) In which period did the income increase continuously?
⑤( 1) In which period did the income decrease continuously?
Vi. (8 points) As shown in the figure, ∠ 1+∠ 2 = 180, ∠A=∠C, try to explain AF ∠ CE.
7. (8 points) A and B want to use roulette to decide who is on duty today. As shown in the figure, it is a turntable that can rotate freely. Turn the turntable. When the turntable stops rotating, if the pointer points to the red area, A is on duty, otherwise B is on duty. Is this game fair to both sides? Why?
(1 1) As shown in figure 1, 2, the quadrilateral ABCD is a square (AD=AB, ∠ A = 90, ∠ ABC = ∠ CBM = 90) M is a point on the extension line of AB. One right-angled edge of the right-angled triangle ruler passes through point D, the right-angled vertex E slides on the edge AB (E does not coincide with points A and B), and the other right-angled edge intersects the bisector BF of ∠CBM at point F.
(1)(9 points) When the midpoint of point E on AB side is as shown in figure 1, and the midpoint of connection point E and AD side is n, please try to explain that NE = BF.
(2)(2 points) When point E is at any position on the AB side as shown in Figure 2, where n is on the line segment AD and NE=BF? There is no need to explain why.
Figure 1 Figure 2
Test answer
First, multiple choice questions
1.D 2。 B 3。 C 4 explosive B 5。 C 6。 B 7。 D 8。 D 9。 C 10。 B
Second, fill in the blanks
1.4 4 2.②③④ 3.①②③
4.5. Degree of central angle of sector and sector area
6.7.2 8.30
9. 15 105 10.8+6(n- 1)
Third,
1.- 1
2. The original formula =, when A =- 1 and B =-2, the original formula =- 16.
Fourth,
1.
2.( 1) throughput is increasing year by year, with a slow growth rate in the first three years and a rapid growth rate in the second two years. The throughput of 20 1 1 is three times that of 2007.
(2) 654.38+600 million yuan.
Five,
1.
2. (1) 65438+the highest in February, with a profit of 5 million yuan, and the lowest in August, with a profit of110,000 yuan.
(2) 2 million yuan
(3)65438+ October
(4) August -65438+ February
(5) 65438+1October-August.
6. Because ∠ 1+∠ 2 = 180.
So DC AB
So ∠A=∠FDC
Because ∠ A = ∠ C again.
So ∠FDC=∠C
in this way
Seven, fairness. ,
(1) Because NDE+AED = 90, BEF+AED = 90.
So ∠NDE=∠BEF
Because BF shares ∠CBM.
So ∠ EBF = 90+45 = 135.
Because AN=AE
So ∠ ane = ∠ aen = 45.
∠DNE = 180-∠ Ane = 135
So ∠EBF=∠DNE
And DN=EB.
So △ dne △ ebf
So NE=BF
(2) when DN=EB.