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Urgent for the exact answer of the third grade mathematics in Mentougou District, Beijing in 2009!
In 2009, Mentougou District unified practice for the first time in Grade Three.

Math test paper grading reference

First, multiple-choice questions (***8 small questions, 4 points for each small question, ***32 points)

Title 1 2 3 4 5 6 7 8

Answer a d b c b c d

Fill in the blanks (***4 small questions, 4 points for each small question, *** 16 points)

Title 910112

answer

- 15 8

III. Answer questions (***5 small questions, ***25 points)

13. (Full score for this small question)

Calculation:

Solution:

= ... 4 points.

= ......................................................... 5 points.

14. (Full score for this small question)

Solving inequality system

Solution: If inequality ① is solved, x < 2. ................................................................................................................................................................

If inequality ② is solved, x >- 1 ..........................................................................................................................................................

The solution set of the original inequality group is-1 < x < 2. .............................................................................................................................................

15. (Full score for this small question)

Prove,

∴, .............................. 2 points.

Say it again,

∴ ............................................ 3 points.

At △ABC and △CDE,

.................................................., 4 points.

∴ BC = 5 points in ...........................................................

16. (Full score for this small question)

Solution:

.........................................., two points.

Three points

..........................................................., 4 points.

When, the original type of ............................................................ 5 points.

17. (Full score for this small question)

Solution: (1)∵ Image passing point of inverse proportional function,

∴ .

∴ The analytical formula of inverse proportional function is .................................................................................................................................................................

This point is on the image of the inverse proportional function,

∴ .

∴ ............................................. 2 points.

(2) When or, the value of the linear function is greater than the value of the inverse proportional function ...................... by 4 points.

(3) The analytical formula of the function image obtained by moving the linear function image to the right by 1 unit length is y =-x ... five minutes.

Iv. Answer questions (***2 small questions, * * 10)

18. (Full score for this small question)

Solution: As shown in the figure, point A is AF⊥BC, and point F is ............................................ 1 min.

∠D=90,

∴ .

Say it again,

The quadrilateral AFCD is a rectangle.

∴ FA = CD = ........................................... 2 points.

In Rt△AFB, ∠ b = 60,

∴BF = af÷tan 60 = 4 ...............................................................................................................................................

∴ AD = FC = BC-BF = 9-4 = 5 ..................................................... 4 points.

In Rt△ADE, ∠ d = 90,

,

∴ .

∴ ...........................................................................................................................................................................

19. (Full score for this small question)

Solution: (1) The straight line CE is tangent to ⊙ o. 。

Proof: As shown in the figure, link OD.

Advertising sharing ∠FAE,

∴∠CAD=∠DAE.

OA = OD,

∴∠ODA=∠DAE.

∴∠CAD=∠ODA.

∴OD‖AC.

∵EC⊥AC,

∴OD⊥EC.

∴CE is the tangent of⊙ O, and ....................................................................................... is 2 points.

(2) As shown in the figure, connect BF.

∵ AB is the diameter⊙ O,

∴∠ Air base =90 degrees.

∫∠C = 90,

∴∠AFB=∠C.

∴BF‖EC.

∴ af: AC = company.

∫AF∶FC = 5∶3,AE= 16,

∴5∶8=AB∶ 16.

∴ AB =10 ........................................................... 5 points.

V. Answer the question (the full mark of this question is 5 points)

20. (The full score for this short question is 5)

Solution: (1) Complete figure 1 and figure 2 ... 2 points.

(Ben)

These 65,438+000 students read three extra-curricular books in one semester on average, and ....................................................................................................... scored 3 points.

3000×3=9 000 .

It is estimated that students in this school read 9000 extracurricular books in one semester. ..............................................................................................................................................................

(3) If you can put forward a positive view according to the chart, score 5 points.

Six, answer (***2 small questions, * * 10)

2 1. (Full score for this small question)

Solution: Class A donated X pieces of stationery and Class B donated Y pieces of stationery. .........................................................................................................................................................

According to the meaning of the question, get 3 points.

Solution ... 4 o'clock.

Answer: Class A donation 120 pieces of stationery, and Class B donation 140 pieces of stationery ........................................................ scored 5 points.

22. (The full score for this short question is 5)

Solution: (1) The three spellings are1... 3 points each.

(2) The area of the parallelogram spelled by the three methods is a fixed value, which is12 .......................................... 4 points.

(3) The perimeters of parallelograms spelled by the three methods are not fixed values, but their perimeters are,

Five points.

Seven, answer the question (this question out of 7 points)

23.( 1) proof: order.

Get delta = =。

No matter m is any real number, it has > 0, that is, △ > 0.

This equation has two unequal real roots.

∴ Whether m is any real number or not, the image of quadratic function has two intersections with the X axis, and .................................................................... scores 2 points.

(2) Solution: The opening of the quadratic function image is upward, and the two intersections with the X axis are on both sides of the point (1, 0).

When x= 1, y = 12+2m+m-7 < 0.

M < 2。 ①3 points.

The univariate quadratic equation about x has two real roots,

∴△= ≥0,m2 ≠ 0。

The solution is m ≥, m≠0. 24 points.

M is an integer,

According to ① and ②, the value of m is 1 ............................................................................................................................................................

(3) Solution: When m= 1, the equation is.

By finding the root formula, we get.

∴ x =-2a- 1 or x =-1................................................................. 6 points.

The equation has a real root greater than 0 and less than 5,

∴0