1. In the function y=x- 1x-2, the value range of the independent variable x is ().

A.x？ 1 b . x & gt； 1 C.x？ 1 and x? 2 D.x？ 2

2. The image with linear function y=-2x+ 1 fails ().

A. first quadrant B. second quadrant C. third quadrant D. fourth quadrant

3.A and B are 20 kilometers apart, both from A to B. In the figure, l 1 and l2 respectively represent the relationship between the distance S (kilometers) traveled by A and B and the time T (hours), and make the following statements: ① B leaves at night 1 hour; ② B catches up with A 3 hours after departure; ③ The speed of a is 4 km/h; (4) B arrives at B first. The correct number is ()

A.4 B.3 C.2 D. 1

4. For the linear function y=kx+k- 1(k? 0), the following statement is true ()

A. When 0

B when k>0, y decreases with the increase of x.

C. when K.

D. The function image must pass through the point (-1, -2).

5. As shown in the figure, the straight line y=23x+4 intersects the X axis and the Y axis at points A and B respectively. Point C and point D are the midpoint of line segments AB and OB, point P is a moving point on OA, and the coordinate of point P with the smallest PC+PD value is ().

A.(-32，0) B.(-6，0)

C.(-3，0) D.(-52，0)

6. The picture shows the sales image of a product in this area for 30 days. Figure ① shows the functional relationship between daily sales volume y (unit: pieces) and time t (unit: days). Figure ② shows the functional relationship between the sales profit z (unit: yuan) and the time t (unit: day) of a product. Known daily sales profit = daily sales? Regarding the sales profit of products, the following conclusion is wrong ()

A. The sales volume on the 24th day is 200 pieces.

B The profit from selling a product on the first day 10 is 15 yuan.

C./kloc-the daily sales profit on 0/2 and 30 is equal.

D the daily sales profit on the 30th day is 750 yuan.

Second, fill in the blanks

7. Suppose that the function y=2x2a+b+a+2b is a proportional function, then a=____, and b = _ _ _.

8. If the image of the linear function y = 2x+b (where b is a constant) passes through the point (1, 5), then the' value of b is _ _ _ _.

9. It is known that (-1, y 1) and (2, y2) are two points on the straight line y=2x+ 1, then y1_ _ y2. (fill in? & gt=? Or? & lt？ )

10. Translate the image with the proportional function y=2x upward by 3 units, and the obtained straight line does not pass through the _ _ _ quadrant.

1 1. The image of the linear function y 1=kx+b and y2=x+a is as shown in the figure, then kx+b >; The solution set of x+a is _ _ _ _ _ _ _.

12. the squares A 1 b1c and A2B2C2C 1 are placed as shown in the figure, with points a1and A2 on the straight line y=x+ 1 and point c/. As we all know.

13. Two people, A and B, run at the same starting point, the same end point and the same direction at the same speed and different speeds. Those who reach the finish line should rest in the same place first. It is known that Party A started 30 seconds earlier than Party B.. In the whole running process, the distance Y (m) between Party A and Party B and the time X (s) when Party A left.

Third, answer questions.

14. the image of linear function y=kx+b passes through m (0 0,2) and n (1 3).

(1) Find the values of k and b;

(2) If the intersection of the image and the linear function y=kx+b and the X axis is A(a, 0), find the value of a. 。

15. If the straight line y= 12x+2 intersects the X axis and the Y axis at two points A and C respectively, then the point P is a point on the straight line in the first quadrant, PB? On the x axis, b is vertical feet, and S△ABC=6.

(1) Find the coordinates of point B and point P;

(2) Make a straight line BQ∨AP pass through point B, intersect with Y axis at point Q, and find the coordinates of point Q and the area of quadrilateral BPCQ.

16. as shown in the figure, in the plane rectangular coordinate system xOy, the straight line y=kx+b intersects the x axis at point a and the y axis at point b, and the coordinate of the midpoint e of the line segment AB is (2, 1).

(1) Find the values of k and b;

(2)P is a point on the straight line AB, PC? The x-axis is at point c, PD? The y axis is at point D. If the quadrangle PCOD is a square, find the coordinates of point P. 。

The probe balloon 17. 1 started from an altitude of 5 meters and rose at the speed of 1 m/min. At the same time, probe balloon No.2 started from the altitude of 15 m and rose at a speed of 0.5 m/min, and both balloons rose at a uniform speed of 50 min. Let the balloon rise time be x min(0? x？ 50).

(1) Fill in the following table according to the meaning of the question:

Rise time/min 10 30? x

The height of the probe balloon 1 /m 15?

What is the altitude /m 30 of the probe balloon 2?

(2) Can two balloons be at the same height at a certain moment? If so, how long did the balloon rise at this time? At what altitude? If not, please explain the reasons;

(3) When is 30? x？ What is the maximum height difference between two balloons at 50 o'clock?

18. As shown in Figure ①, a passenger takes the high-speed train from A to C via B, and the train travels at a constant speed. Fig. ② shows the functional relationship between the distance y (km) from the distance b and the travel time x (hours).

(1) Fill in the blank: the distance between Party A and Party C is _ _ _ _ _ _ kilometers;

(2) Find the functional relationship between the distance Y between the high-speed train and B and the travel time X, and write the range of X. 。

19. As shown in the figure, A (0, 1), M (3 3,2), N (4 4,4), the moving point P starts from point A and moves along the Y axis at a speed of/kloc-0 per unit length per second, passing through point P L: Y =-X+B.

(1) When t=3, find the analytical formula of L;

(2) If points M and N are located on opposite sides of L, determine the value range of t;

(3) When writing the value of t directly, the symmetry point of point M about L falls on the coordinate axis.

20. There are 30 agricultural machines in City A and 40 in City B.. Now, all these agricultural machinery will be transported to C and D townships, and the dispatching task will be contracted to a transportation company. It is known that township C needs 34 agricultural machines and township D needs 36 agricultural machines. The cost of transporting agricultural machinery from A city to C and D towns is 250 yuan/Taiwan and 200 yuan/Taiwan respectively, and the cost of transporting agricultural machinery from B city to C and D towns is 6544 respectively.

(1) Let City A transport agricultural machinery X to Township C, and the total cost of transporting all agricultural machinery is W yuan. Find the functional relationship between W and X, and write the range of independent variable X;

(2) At present, the transportation company requires that the total cost of transporting all agricultural machinery should not be less than 16460 yuan, so how many different transportation schemes are there? Design these schemes;

(3) Now the transportation company has decided to reduce the agricultural machinery transported from A city to C township by A yuan (A? 200) As a discount, other expenses remain unchanged. How to allocate and transport to minimize the total cost?

Answer:

I. 1-6 ccbcac

Two. 7.23 - 13

8.3

9.& lt

10.4

1 1.x & lt-2

12.(3,2)

13. 175

Third,

14. solution: (1) b=2, k+b=3, k= 1b=2.

(2) In the resolution function y=x+2, let y=0, then x=-2,? a=-2

15. solution: (1) b (2,0), P (2 2,3)

(2)Q(0,-1), s quadrilateral BPCQ=6.

16. solution: (1)k=- 12, b=2.

(2) The coordinate of point P is (43,43) or (-4,4).

17.( 1) 35 x+5

20 0.5x+ 15

(2) (2) Two balloons can be located at the same height. According to the meaning of the question, x+5=0.5x+ 15, and the solution is x=20. X+5=25, then the balloon rose for 20 min, all at the height of 25 m.

(3) When is 30? x？ 50 o'clock, as can be seen from the meaning of the question, the altitude of the balloon 1 is always higher than that of the balloon 2. If the altitude difference between two balloons at the same time is y meters, then y = (x+5)-(0.5x+15) = 0.5x-10, ∫ 0. Y increases with the increase of X. When x=50, Y gets the maximum value of 15, that is, the height difference between two balloons is 15 m at most.

18.( 1) 1050

(2) When 0? x？ At 3 o'clock, let the functional relationship between the distance y between the high-speed train and B and the running time x be y=k 1x+b 1, and substitute (0,900) and (3,0) into B1= 900,3k1+B/kloc. 3=300 (km/h)， 150？ 300=0.5 (hour), 3+0.5=3.5 (hour), then the coordinate of point A is (3.5,150); When 3

19.( 1) the straight line y=-x+b and the y axis are at point P(0, b), b= 1+t, and when t=3, b=4. y=-x+4

(2) When the straight line y=-x+b passes through m (3 3,2), 2=-3+b, and b=5,? 5= 1+t，？ t = 4； When the straight line y=-x+b passes through n (4 4,4), 4=-4+b, and b=8, 8= 1+t，？ t=7，？ four

(3) When t =1,it falls on the y axis; When t=2, it falls on the x axis.

20. (1) w = 250x+200 (30-x)+150 (34-x)+240 (6+x), that is, w =140x+12544. 30)

(2) 140x+ 12540 According to the meaning of the question? 16460,? x？ 28，∫x？ 30,? 28? x？ 30,? There are three different transportation schemes: A city to C township 28, A city to D township 2, B city to C township 6, B city to D township 34; 29 units were transported from City A to Township C, 1 unit was transported from City A to Township D, 5 units were transported from City B to Township C, and 35 units were transported from City B to Township D; 30 units were transported from City A to Township C, 0 units from City A to Township D, 4 units from City B to Township C, and 36 units from City B to Township D..

(3) w = (250-a) x+200 (30-x)+150 (34-x)+240 (6+x) = (140-a) x+12544. When a= 140 and W= 12540, the cost of each scheme is the same; When 140