People's education printing plate eighth grade mathematics volume one final examination paper
A, multiple-choice questions * * * 3 points for each small question, *** 18 points * * *
There are four answers to each question below, and only one is correct. Fill in the brackets after the question with the code letters of the correct answer.
The reciprocal of 1 It is * * * *
A.B. C. D。
2. The angular bisector AD and BC of * * * intersect at point D, and the distance from point D to AB is * * * *.
A. 1
3. The following operation is correct * * * *
A.B.
C.D.
4. Points with equal distances to three sides of a triangle are * * * * * * of the triangle.
A. the intersection of three center lines
C. Intersection point of perpendicular bisector of three sides D. Intersection point of three angular bisectors
5. The image of linear function is roughly * * * * * *
6. As shown in the figure, it is known that,, and are the intersections of high sums, so the length of the line segment is * * * * * *.
A.B.4 C. D.5
Second, fill in the blanks * * * 3 points for each small question, ***27 points * * *
7. Calculation:.
8. As shown in the figure, the numbers represented by two points on the number axis are 1 and respectively, and the symmetry point of a point is a point, then the number represented by the point is.
9. With the elevation, the oxygen content in the air is directly proportional to the atmospheric pressure. If yes, please write the functional relationship with.
10. Factorization:
1 1. As shown in the figure, if the image of a linear function passes through point A and point B, the solution set of the inequality about x is.
DrawingNo. 1 1 drawingNo. 13
12. If it is known, then _ _ _ _ _ _ _.
13. As shown in the figure, there are several rectangular cards of Class A, Class B and Class C. If you want to spell out a large rectangle with a length of * * * A+2B * * and a width of * * A+B * *, you need a card of Class C. 。
14. The straight line passes through a point and a point on the positive semi-axis of the shaft. If * * * is the coordinate origin and the area of * * * is 2, the value of is.
15. In the plane rectangular coordinate system, the known point is the moving point on the axis. When it is an isosceles triangle, the number of values is.
Iii. Answer * * * There are 8 small questions in this big question, ***75 points * * *
Scoring reviewer
16.***8 points * * * calculation:.
17.***8 points * * As shown in the figure, there are two grids, the side length of each small square in the grid is 1, and each grid has a trapezoid. Please draw a line segment in Figure 1 and Figure 2 respectively, and meet the following requirements:
One endpoint of the * *1* * * line segment is the vertex of the trapezoid, and the other endpoint is on the lattice point on one side of the trapezoid;
***2*** Divide the trapezoid into two figures, one of which is an axisymmetric figure;
* * * 3 * * Figure 1 is not equal to the axisymmetric figure in Figure 2.
Scoring reviewer
18.***9 points * * *1* * Decomposition factor:.
***2*** Simplify before evaluating:, where.
Scoring reviewer
L9。 ***9 minutes * * * Place two right triangles with an angle of 45 as shown in the figure. Point D is on BC, and the extension line connecting BE, AD and AD intersection is at point F. 。
Evidence: AF⊥BE.
20.***9 points * * * In the urban area, the functional relationship between taxi price * * * yuan * * and distance * * * kilometers * * * is as shown in the figure.
* * *1* * Please write two pieces of information according to the picture;
* * * 2 * * Xiaoming took a taxi home from school and spent 13 yuan to find the distance from school to Xiaoming's home.
2 1.*** 10 Point * * As shown in the figure, in an equilateral graph, the points are on the sides respectively, and the points intersect each other.
*** 1*** Verification:;
* * 2 * * degree.
22.*** 10 points * * * Recreation Company has the same machine platform and platform in two places, and now it will be transported to Platform A and Platform B. The expenses for transporting from two places to two places are as follows:
A * * * Yuan/Taiwan * * * B * * * Yuan/Taiwan * * *
land
* * *1* * If it is transported from the ground to Platform A, please find out the functional relationship between the total cost * * * Yuan * * and Platform * * * *;
* * * 2 * * Please design an optimal transportation scheme for the amusement company to minimize the total cost and explain the reasons.
23.*** 12 points * * * The straight line distances on both sides of the known points are equal, and.
* * * 1 * * as shown in figure1,if you click the edge, verify:
* * * 2 * * As shown in Figure 2, if you click Inside, please verify:
***3*** If the point is outside, is it true? Please draw a picture.
People's education printing plate eighth grade mathematics volume one final examination paper answer
A, multiple-choice questions * * * 3 points for each small question, *** 18 points bb bb bb
Second, fill in the blanks * * * 3 points for each small question, ***27 points * * *
7., 8., 9., 10.， 1 1 . x & lt； 2, 12., 13.3, 14.2,
15.4.
Third, answer questions.
16. solution: original formula = ***6 points * * *
***8 points * * *
17. Solution: The following solutions are provided for your reference.
* * * draw 1 species, 4 points; Draw 2 kinds correctly and get 8 points * * *
18. * * *1* * Solution:. ***4 points * * *
***2*** Solution: Original formula =
=.***4 points * * *
When, the original formula =. ***5 points * * *
19. solution: * *1* * proof: in △ACD and △BCE,
AC=BC，
∠DCA=∠ECB=90，
DC = EC,
∴△ACD?△BCE * * * SAS * * 5 points
∴∠DAC =∞∠ebc. 6 points
∫∠ADC =∠BDF，
∴ ∠EBC+∠BDF=∠DAC+∠ADC=90。
∴∠ BFD = 90.8。
∴ AF⊥BE.9 points
20. solution: * *1* * * 5 yuan within 0 to 2 kilometers; Add 1 yuan after 2km. Add 2 points for every 0.625km increase.
* * * The answer is not unique * * *
***2*** Let the expression of the function be. According to the meaning of the question, score 3 points
Solution: .7 points.
Substitute the above formula and get .8 points.
So Xiaoming's home is 7 kilometers away from school.
2 1.* * 1 * * Prove that it is an equilateral triangle,
and
4 points
5 points
***2*** is solved by * *1* * *,
Get 6 points
10 point
22. Solution: * *1* * *; 5 points
***2*** Know from * * 1 * * *: total freight.
Another 8 points
With the increase of, also increased, when, * * * yuan * * 9 points.
The company needs at least 14800 yuan freight to complete the above transportation plan. The best scheme is as follows: the first place is 3 stations, the second place is 14 stations, and the first place is 15 stations. 10.
23. Certificate: * * *1* * * was done separately, and it was vertical.
Judging from the meaning of the question,
Therefore. 3 points
***2 * * points respectively, vertical ruler respectively,
Judging from the meaning of the question,
In and,
You know again, 9 points
Solution: * * * 3 * * * is not necessarily true. 10.
* * * Note: When the line where the bisector is located coincides with the perpendicular bisector of the side, there is; Otherwise, as shown in the example figure *** 12.