Test paper, multiple-choice questions (3 points for each small question, 30 points for * * *)
1, if 2Y-7X = 0, x: y equals ()
A.2:7 B. 4:7 C. 7:2 D. 7:4
2, polynomial factorization ()
X2？ b . x2+ 1 c . x2+XY+Y2 d . x2-4X+4
3. Simplify the result of ()
AX+Y BX-Y CY-x depth. - XY
4. The following conditions are known: because the straight line L 1‖L2 () cannot be judged.
A.∠ 1 =∠3b .∠2 =∠3c .∠4 =∠5d .∠2+∠4 = 180
In our school, 5800 students in Grade 8 took the mid-term math exam, and 200 students took part in math statistics. Make the following judgments: ① This survey is a sampling survey; ②800 students are average; ③ Each student's math score is individual; ④ A total of 200 students; ⑤ Sample size of 200 students. Including the correct judgment ()
A. 1 a b.2c.3d.4
6. Figure △ABC∠AED =∠B, DE = 6, AB = 10, AE = 8 BC long ().
AB CD
(Figure 4) (Figure 6)
7, the following proposition belongs to the false proposition is ()
A. if AB = 0, then A = B = 0 B if AB >；; 0, then > b
C. if AB
8. related inequality x (1) × >; +1 < 1 of x, then the value of the solution is set in the range? ()
AA 1da & gt； - 1
9. Agricultural Development Bank, trapezoidal ABCD, AC and BD intersect in O, if ADBC? = 13, then the following conclusion is correct ()
△COD = 9S△AOD BS△ABC = 9S△ACD CS△BOC = 9S△AOD DS△DBC = 9S△AOD
10, the categories of awards awarded by students of a class at the award ceremony are shown in the following table:
* * * Twenty-eight students in the whole class won the prize. 13 Only the students who got two prizes in return won the prize ().
3 B. 4 C. 5 D. 6
Fill in the blanks (3 points for each small question, 24 points for * * *)
1 1, the inequality of this solution;
The algebraic value of 12 is equal to zero, then x =
13, factorization: =
Figures A and B, when the pond spacing is two, link AC and BC outside the selected point C AB, and determine their midpoints M and N respectively. If Mn =15m is measured, then the distance between point A and point B.
& ltBR/ (Figure) Question 14 (Figure 15) (Figure 17) (Figure 18)
15, at □ABCD, e is the midpoint of CD, AE and BD intersect at point o, and S△DOE = 12 cm2, then s is cm2.
△AOB is equal to 16, and the full score is 100 in the math exam. Li Huha and Wu Sha at the same table discuss the calculation of test scores. Li Hua said, "Our score is 160, and Wu Shan said," Our score difference is 60. Then the following two propositions: ① Two statements are correct, ② At least one person is wrong. The real proposition is (fill in the serial number).
17 is shown in the figure, and the following conclusions are drawn: (1) ∠ a > ∠ACD②∠b+∠ACB = 180-∠A； ③ The ∠B+∠ b of ③ACB is correct (fill in your correct serial number).
18, as shown in the figure, in the process of graphic splicing? Any three vertices of four squares,,,,,, 10 will always be an isosceles triangle. Are you willing to communicate with others? If you like, please write a short description under your inquiry process (the agile and reasonable conclusion is correct, add 2 points, but it will not exceed the total score 100): _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
______________________________________________________________________________ 。
III (6 points for each small question, 12 points)
Inequalities of 19 solution
& gt
20, X = Y = demand value.
Four (6 points in the test paper, *** 18 points)
2 1, in order to understand the physical condition of middle school students. After the rope skipping test of the eighth grade students in a middle school is completed, the data obtained by drawing lots through frequency distribution are displayed in the form of histogram. The known patterns in the first three groups of frequencies are 0. 1, 0.3 and 0.4 from left to right, and the first group of frequencies is 5.
(1) the fourth group _ _ _ _ _ _ _ _
(2) The frequency of students participating in this test is _ _ _ _ _ _ _ _ people's scores.
(3) Which set of data does it belong to? how much is it?
(4) Find the percentage of total test.
Students scored more than 100 times (100 times).
22. In the activity of striving for a national sanitary city, the urban youth commando decided to pile a pile of garbage weighing100t in Qingyun. After the start, the residents nearby took an active part in voluntary labor and cleaned up the garbage, which was twice as fast as originally planned. As a result, the task was completed four hours ahead of schedule, requiring the originally planned "Youth Commando to dismantle and transport several tons of garbage every hour"?
23. A school cafeteria plans to buy 12 tables, two shopping malls and some chairs from A and B. At present, the quotation for each table of the same model is that chairs made in 200 yuan are provided to 50 yuan. In the shopping mall: For every set of dining tables and chairs purchased, Shopping Mall B stipulates that all dining tables and chairs are sold at a discount of 15%. So, under what circumstances do you buy more discounts in shopping malls?
(This topic is 10 24. It is known that a rectangular piece of paper similar to ABCD is folded along EF. )
Point D coincides with point B, and point C falls at the position of point C, If ∠ 1 = 60, AE = 1.
(1) Find ∠∠3 degrees;
(2) Find the area? A rectangular piece of paper ABCD