New people's education printing plate eighth grade second volume mathematics final examination questions
First, multiple-choice questions (3 points for each small question)
1. If the following numbers are irrational, they are ().
A.B.﹣ C？ D.﹣
2. The following statement about quadrilateral is true ()
A. A diamond with four equal corners is a square.
B. The quadrilateral with diagonal lines perpendicular to each other is a diamond.
C. A parallelogram with two equal sides is a diamond.
D. two quadrangles with equal diagonals are diamonds.
3. The value range of X that makes the algebraic expression meaningful ()
A.x & gt2 B.x？ 2c . x & gt； 3 D.x？ 2 and x? three
4. As shown in the figure, rotate △ABC clockwise around point C by 50? And get delta a? b？ c？ What if? A=45？ ,? b？ = 1 10? And then what? BCA？ The degree is ()
.55 caliber? B.75？ C.95？ D. 1 10？
5. The known points (-3, y 1) and (1, y2) are on the straight line y = kx+2 (k
a . y 1 & gt； y2 B.y 1=y2 C.y 1
6. As shown in the figure, in quadrilateral ABCD, diagonal AC and BD intersect at point E,? CBD=90？ , BC=4, BE=ED=3, AC= 10, then the area of quadrilateral ABCD is ().
12 C.20 D.24
7. The solution set of inequality group is x>2, so the range of m is ().
Morning & lt 1 B.m? 1 C.m？ 1d . m & gt； 1
8. If +| 2a-b+ 1 | = 0, the value of (b-a) 20 16 is ().
A.﹣ 1 b . 1 d.﹣520 15
9. As shown in the figure, select a small square marked with serial number 12344 in the grid paper and paint it black, so that it and the new figure formed by the shaded part in the figure are the central symmetrical figure. The number of the small square is ().
A.① B.② C.③ D.④
10. Connect the midpoint of each side of a quadrilateral in turn to get a rectangle, then the following quadrilateral satisfies the condition ().
① parallelogram; ② diamond shape; ③ Rectangular; A quadrilateral with diagonal lines perpendicular to each other.
A.①③ B.②③ C.③④ D.②④
1 1. Given that A, B and C are three sides of △ABC and satisfy (A2-B2) (A2+B2-C2) = 0, its shape is ().
A. right triangle B. isosceles triangle
C. isosceles right triangle D. isosceles triangle or right triangle
12. As we all know, the weight of tomatoes sold by fruit farmers is linearly related to the price. Today, Xiaohua bought a bamboo basket of tomatoes from a fruit farmer, with a total weight of 15 kg. The price of tomatoes is 26 yuan. If he buys another 0.5 Jin of tomatoes, he will have to pay more 1 yuan. What is the weight of the empty bamboo basket? ( )
A. 1.5
13. As shown in the figure, in? In ABCD, diagonal AC and BD intersect at point O, and the intersection point O is EF? AC intersects BC at point E and AD at point F, connecting AE and cf, then the quadrilateral AECF is ().
A. trapezoid b rectangle c diamond d square
14. Known xy >；; 0, the correct result of simplifying the quadratic root x is ()
A.B. C.﹣ D.﹣
15. One Sunday afternoon, Xiao Qiang and his classmate Xiaoying met at a bus stop, and they planned to go back to school together. Xiao Qiang started from home and walked to the station first. When Xiaoying arrives, they go back to school by car together. The dotted line in the figure shows the functional relationship between the distance y (km) from Xiao Qiang's home and the time x (min) spent. The following statement is wrong ().
Xiao Qiang takes 20 minutes by bus.
Xiao Qiang waited for Xiaoying at the bus stop for 10 minutes.
The average speed of the bus is 30 kilometers per hour.
Xiao Qiang walked 2 kilometers from home to the bus station.
16. The original price of a commodity is 500 yuan, and it was sold in 900 yuan. To keep the profit not less than 26%, you can at least hit ().
A.60% off B.70% off C.20% off D.10% off
17. As shown in the figure, if the abscissa of the intersection of the straight line y =-x+m and y=x+3 is -2, then the inequality about x-x+m >; x+3 & gt； The value range of 0 is ()
A.x & gt﹣2 b . x & lt； ﹣2 C.﹣3