Class name _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
First, multiple choice questions
1, if the algebraic expressions 7-2x and 5-x are reciprocal, then the value of x is ().
A 4 B 2 C D
2. As shown in the figure, AB∥ED, then ∠ A+∠ C+∠ D = ()
180
3, the following conditions, can't determine the triangle congruence is ()
A, trilateral equality; B, two sides and an angle are equal.
C, the opposite sides of one of the two angles are correspondingly equal; D, the two corners and their clamping edges are correspondingly equal.
Xiao Ming used a uniform coin to test, and the results of the first seven throws were from bottom to top. If the probability of the eighth throw is recorded as p, then ()
A, P=0.5 B, p < 0.5c, p > 0.5d, uncertain.
5. A class is organizing students to discuss how thick 1 piece of paper is.
The following four viewpoints have emerged, and what you think is more reasonable and feasible is ().
A, directly measure the thickness of 1 sheet with a triangular ruler.
B, first use a triangular ruler to measure the thickness of two pieces of paper of the same type.
C, first measure the thickness of 100 sheets of the same type of paper with a triangular ruler.
D, first measure the thickness of 1000 sheets of the same type of paper with a triangular ruler.
6, the following statement is wrong ()
A. The midline, angle bisector and height line of a triangle are all line segments;
B, the sum of internal angles of any triangle is180;
C triangles can be divided into equilateral triangles and isosceles triangles according to their sides;
The outer angle of a triangle is greater than any inner angle.
7. Given that three sides of a triangle are 2 and 4, the range of values is ().
A, B, C, D,
8, in the triangle, if, it is ()
A, right triangle B, acute triangle C, obtuse triangle D, all of the above are wrong.
9. When a car is driving on the expressway at an average speed of 60 km/h, the relationship between its distance S (km) and its time T (h) is ().
A, B, C, D,
10, the symmetry axis of regular pentagon * * * has ()
Many articles
1 1, if one side of an isosceles triangle is equal to 3 and the other side is equal to 6, then its circumference is equal to ().
A, 12 B, 12 or 15 C, 15 or 18 D, 15.
12. Among the following figures, the one that is not axisymmetric is ().
A B C D
Second, fill in the blanks
The coefficient of the third term of 1 and polynomial 32b+2b–1is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
2. If the bottom angle of the isosceles triangle is 36, then the top angle of the isosceles triangle is _ _ _ _ _.
3. What is the probability of the following four events? Fill them in the horizontal line at the back.
Event A: If you can walk 80 kilometers in an hour, then P (a) =;
Event B: An ordinary dice, if you roll it twice and the sum of its points is greater than 10, then P (b) =;
Event C: If the sum of two numbers is negative, then one of them must be negative, then P(C)=.
4. In the chapter "Relationship between Variables", the "variables" we study refer to independent variables and dependent variables, and there are usually three ways to express their relationship, namely,, and.
5, as shown in the figure, there is a triangular land, and now it is required to pass three.
Draw a line segment at the vertex of an angle and divide its area equally.
How do you think this line segment should be drawn?
__________________; Why? _____________________。
6. Put a rectangular piece of paper with letters and numbers "A, B, C, D, E, 1, 2, 3, 4, 5" on the table in front of a flat mirror. The letters and numbers on the paper in the mirror are unchanged.
7. As shown in the figure, given DE is the middle vertical line of AC, AB= 10cm, BC= 1 1cm, and the circumference of δ δδABD is _ _ _ _ cm.
8. As shown in the figure, ∠A=20, ∠C=40 and ∠ADB=80, ∠ Abd = _ _ _ ∠ DBC = _ _ _, and there are * * * isosceles triangles in the figure.
9. As shown in the figure, the symmetry points of point P about OA and OB are C and D, respectively. Connected CD, OA intersects in M and OB intersects in N. If the circumference of PMN is 8 cm, CD is _ _ _ cm.
10, a bamboo pole is 3.649 meters long. The tenth place is rice; The diameter of silver atom is 0 .0003 micron, which is equivalent to meters.
1 1. In today's math class, the teacher talked about the addition and subtraction of polynomials. After school, Xiao Ming came home and took out his class notes. He carefully reviewed what the teacher said in class. He suddenly found a problem: (-x2+3xy-y2)-(-x2+4xy-y2) =-x2 _ _+y2 space.
Third, drawing questions
As shown in Figure (3-2), there is a ball A on the billiard table. How can I get there?
Hit the ball a against the frames MN and NP in turn and hit it.
Ask for the ball B. (Draw a schematic diagram, don't write a picture, keep drawing.
Tracking)
Fourth, answer questions.
1 、( 1)2(m+ 1)2-(2m+ 1)(2m- 1)
(2)
(3), in which
2. As shown in Figure (IV- 1), in △ABC, ∠B=40, ∠BCD= 100, EC is divided into ∠ACB, and the degrees of ∠A and ∠ACE are found.
Verb (abbreviation of verb) proves the problem
1, as shown in figure (V- 1), points b, f, c and e are on the same straight line, FB=CE, AB∑ED, AC∑FD,
Verification: AB=DE, AC=DF.
2. As shown in the figure, it is known that they are all equilateral triangles, and BD and CE intersect at point F. ..
(1) verification: BD=CE
(2) Find the degree of acute angle.
Six, explore the problem
Two people (A riding a motorcycle and B riding a bike) travel from City A to City B, with a distance of100km, as shown on the right, which shows the relationship between distance and time when they leave City A. ..
1. What are the average speeds of Party A and Party B during this journey?
2. According to the picture, what information can you get about A and B travel?
Note: Pay attention to the following requirements when answering 2:
(1) Please provide at least three pieces of relevant information. For example, according to the picture, Party B left 4 hours earlier than Party A (or Party A left 4 hours later than Party B). (2) Do not provide the information listed in (1).
3. Exploration and application of multiplication formula.
(1) As shown in the left figure, the area of the shaded part can be found as (written as the square difference of two numbers);
(2) As shown in the figure on the right, if the shadow part is cut off and reassembled into a rectangle, its width is, its length is, and its area is (written in the form of polynomial multiplication).
(3) Comparing the shadow areas of the left and right images, we can get the multiplication formula (expressed by formula).
(4) Use the formula you get to calculate the following questions:
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