The total score of the topic is one two three four five six seven.

score

I. Fill in the blanks (3 points for each question, 30 points for * * *)

1, the value range of the independent variable x in the function y =+ is.

2. The diameter of cold virus is 0.000000 12m, which is expressed by scientific notation.

3. Calculation:; ;

4. If x2+2(m-3)x+ 16 is completely flat, the value of m is equal to.

The simplest common denominator of 5 is.

6. As a result of simplification.

7. At that time, the score was 0.

8. Fill in the blanks: x2+()+14 = () 2;

()(-2x+3y)=9y2—4x2

9. If the image of linear function y = (2-m) x+m passes through the first, second and fourth pixels, the value range of m is _ _ _ _ _, and if its image does not pass through the second quadrant, the value range of m is _ _ _ _ _.

10. In order to encourage citizens to save water, a water supply company in a certain city adopted a segmented charging standard. The functional relationship between the monthly water fee y (yuan) and the water consumption x (ton) of a city resident is shown in the figure. Please answer the charging standard of the water supply company by observing the function image: if the water consumption does not exceed 5 tons, the water fee is _ _ _ _ _ _ _ _ yuan/ton; If the water consumption exceeds 5 tons, the water fee for the excess part is _ _ _ _ _ _ _ _ _ _ yuan/ton.

Second, multiple-choice questions (3 points for each question, ***30 points)

1 1, in the following formula, the deformation from left to right is factorized ().

a 、( x- 1)(x-2)=x2-3x+2 B、x2-3x+2=(x- 1)(x-2)

c，x2+4x+4 = x (x-4)+4d，x2+y2 = (x+y) (x-y)。

12, simplification: the result is ()

A.B. C. D。

13, Xiao Mahu only got one question right in the following calculation, and the right question is ().

A, B, C, D,

14. Dig a small square (>) with a side length in a square with a side length of, and make the rest into a rectangle (as shown in Figure B). According to the fact that the shaded areas in the two pictures are equal, () can be verified.

A.

B.

C.

D.

After the expansion of 15, the polynomial (x+m) (x-3) does not contain the linear term of x, and the value of m is ().

A.m=0 B. m=3 C. m=-3 D. m=2

16, point P 1(x 1, y 1), point P2(x2, y2) is two points on the image of linear function Y =-4x+3, and X 1 < X2, then y/kloc.

a . y 1 > y2 b . y 1 > y2 > 0 c . y 1 < y2 d . y 1 = y2

17, the following approximate result is correct ()

A, B,

C, D,

18, if the roots of solving the fractional equation increase, then the increase of roots may be ().

A, -2 B, 3 C, 3 or -4 D, -4

19. If point a (2 2,4) is on the image of the function, then the following point is () on the image of the function.

A (0，-2) B(，0) C (8，20) D(，)

20. How far is Xiao Min's home from school? One day, Xiao Min goes to school by bike from home. At first, she was driving at a constant speed of 100 meters per minute. When she was caught in a traffic jam, she was delayed for a few minutes. Then she kept moving at a constant speed of 100 meter per minute until she reached school. Do you think the function picture between the distance and time of Xiao Min's home is roughly ()?

Three. Calculation questions (4 points for each question, *** 12 points)

1、2(m+ 1)2-(2m+ 1)(2m- 1)2、

Four, factorization (4 points per question, *** 12 points)

1、8a3b2+ 12ab3c 2、a2(x-y)-4b2(x-y)

3、2x2y-8xy+8y

Verb (abbreviation of verb) evaluation (5 points for this question)

In class, Miss Li gave such a question:

It is known that finding algebraic expressions is too complicated for Xiao Ming to substitute directly into calculation. Please help him solve it and write down the specific process.

6. Solve the following fractional equation: (5 points for each question, *** 10)

1、 2、

Seven, answer (1, 2 questions each 6 points, 3 questions 9 points)

1 A tour group leaves the hotel at 8: 00 a.m. and takes a bus to a famous tourist attraction, with a distance of 180 km. The relationship between the distance s (kilometers) from the hotel and the time t (hours) can be represented by the dotted line in fig. 6. According to the information provided by the picture, answer the following questions:

(1) What is the average speed of tour groups to the scenic spots?

(2) How many hours did the delegation stay in the tourist attractions?

⑶ Find the functional relationship between S (km) and time t (hour) on the way back, and find the range of independent variable t. ..

2. Inspired by the story of "crow drinking water", Xiao Ming used a measuring bucket and a ball with the same volume to do the following:

Please answer the following questions according to the information given in Figure 2:

(1) into the small ball measuring bucket, the water level will rise _ _ _ _ _ _ _ _;

(2) Find the linear functional relationship between the water level in the measuring cylinder () and the number of balls (without requiring the range of independent variables);

(3) When at least several balls are put into the measuring cylinder, does the water overflow?

3. In response to the national call of "home appliances going to the countryside", a refrigerator factory plans to produce two models of refrigerators 100. According to the budget, after all the refrigerators are sold, the profit can be no less than 47,500 yuan and no more than 48,000 yuan. The production costs and selling prices of the two models are as follows:

Type a and type b

Cost (RMB/set) 2200 2600

Price (RMB/set) 2800-3000

(1) What kinds of production schemes does the refrigerator factory have?

(2) Which scheme produced by refrigerator factory has the lowest input cost? After "home appliances go to the countryside", farmers can enjoy a government subsidy of 13% when purchasing home appliances (refrigerators, color TVs and washing machines). How much does the government need to subsidize farmers under this plan?

(3) If the production is carried out according to the scheme in (2), the refrigerator factory plans to use all the profits to buy sports equipment, experimental equipment and office supplies to support a Hope Primary School. At most, buy four sets of sports equipment, each set of sports equipment is 6000 yuan, each set of experimental equipment is 3000 yuan, and each set of office supplies is 1.800 yuan. If all the money is used up and all three things are bought,