Who has taught the eighth grade first volume mathematics midterm paper of the press? Send it

Mathematics midterm examination questions of grade eight in the first semester
Name of class student number
1、 Multiple choice questions (3 points for each sub question, 30 points in total)
1. In the following real numbers: | - 3 |, 0.8080080008 There are () irrational numbers
A、1 B、2 C、3 D、4
2. The number corresponding to the point on the number axis is ()
A. Real number B, rational number C, irrational number d, integer
3. The following proposition is correct ()
A. The two groups of parallelograms with opposite sides parallel to each other are rectangle B, and the parallelograms with one right angle are rectangles
C. A quadrilateral with two right angles is a rectangle D, an angle is a right angle, and a group of paralleled quadrilaterals are rectangles
4. The diagonal of a square has ()
A. Bisection B, vertical C, equal D, vertical, bisection and equal
5. The following patterns are both centrosymmetric and axisymmetric ()
A. B. C. D.
6. The following statement is wrong ()
A. 1 is the arithmetic square root of (- 1) 2, and the cube root of B, C and - 27 is - 3
D、
7. From 8:55 to 9:15, the minute hand of the clock turns at an angle of, and the hour hand turns at an angle of
A. 120 0、10 0 B. 30 0、 15 0 C. 12 0、60 0 D. 10 0、120 0
8. The correct of the following is ()
A. B. C. D.
9. As shown in the figure, △ ABC in a square grid. If the side length of the small grid is 1, △ ABC is ()
A. Right triangle B. acute triangle
C. Obtuse triangle D. none of the above answers is correct
10. If the three sides of a right triangle are expanded by the same multiple, the resulting triangle is ()
(A) Acute triangle (b) obtuse triangle (c) right triangle (d) arbitrary triangle
2、 Fill in the blanks: (2 points for each blank, 20 points in total)
1. What is the square root of
2. The length of a line AB is 3cm. After translating it 4cm horizontally, the line CD is obtained,
What is the length of a CD
3. If the sum of the inner angles of a polygon is equal to three times the sum of its outer angles, it is a polygon
4. In RT △ ABC, if ∠ C = 90 and AC = 5cm, ab = 13cm, then BC = cm
5. If the ratio of two adjacent angles of a parallelogram is 3 ∶ 2, the degrees of the two angles are
6. If AC and BD are diagonals of the diamond, and AC = 6cm and BD = 8cm, the area of the diamond is cm2
7. If △ ABC and △ DCE are equilateral triangles, then in the right figure, △ ace
Around__ Point__ Rotation__ The results show that △ BCD can be obtained
8. The circumference of rectangle ABCD is 56cm, and the diagonal lines AC and BD intersect at point o,
If the perimeter difference between △ OAB and △ OBC is 4cm, then the rectangle ABCD
The shorter side length in is
9. If the three sides of ABC are a, B, C respectively, and a, B, C
If (a + b) 2-2ab = C2, then △ ABC is a triangle
10. As shown in figure (1), take the center of the pattern on the left as the center of rotation
The right pattern can be obtained by rotating the pattern in the direction
3、 Calculation
4、 Drawing questions (6 points in total)
Rotate the left image counterclockwise around o point, and translate the right image 5 spaces to the right
5、 Answer questions (30 points in total)
1. (5 points) when someone wants to cross a river from point a, due to the influence of current, the actual landing site is not clear
C deviates 240 meters from the point B to reach. As a result, he actually swam 510 meters in the water
2. In rectangular ABCD, the diagonal lines AC and BD intersect at O, ab = OA = 4cm,
How long is BD and ad? (5 points)
3. As shown in the figure, in the parallelogram ABCD, points E and F are on the diagonal AC, and AE = CF
Proof: quadrilateral BEDF is parallelogram (6 points)
4. Known: as shown in the figure, in △ ABC, ab = AC, ad BC, the perpendicular foot is D, an is the bisector of △ ABC outer angle cam, CE an, the perpendicular foot is e, connecting De to AC at f (9 points)
(1) Verification: the quadrilateral adce is a rectangle
(2) Verification: DF ‖ AB, DF = ab
(3) When △ ABC meets what conditions, the quadrilateral adce is a square? Briefly describe your reasons

Now there is an isosceles triangle, two base angles are equal. The vertex angle has an outer angle, the outer angle has an angular bisector, and the angular bisector bisects the outer angle. Is the outer angle of the triangle equal to the sum of two non adjacent inner angles? So the outer angle is equal to the sum of two base angles. How can we prove that half of the outer angle is equal to the sum of one base angle?
Half of the outer angle is the angle between the bisector of the outer angle and one side. I know these two angles are equal, but why are they equal? I know. Come on

Please draw a diagram according to what I said!
If AB = AC, ad is the bisector of CAE at the outer angle of ∠ BAC in triangle ABC, it is proved that ∠ CAD = ∠ B
It is proved that: ab = AC, then ∠ B = C;
(theorem of sum of internal angles of triangles)
∠ CAE + ∠ BAC = 180 ° (definition of horizontal angle)
Then, B + C = CAE and ad divides CAE equally
That is, 2 ∠ B = 2 ∠ CAD, then ∠ CAD = ∠ B

Fill in the blanks with isosceles triangle
The waist ab of the isosceles triangle ABC is 10cm. The vertical bisector of AB intersects the other waist at point D. if the circumference of △ BCD is equal to 17cm, the length of BC is equal to 17cm___________ .
Great Xia, please note that although it's a question to fill in the blanks, it's better to have the steps to solve it

so easy !
Link BD
(the other waist is AC)
Because the vertical bisector of AB intersects the other waist at D, AB and E
Then triangle AED congruent triangle BDE (SAS)
So BD + DC = AC = AB = 10cm
Because the perimeter of △ BCD is 17cm
So BC = 7cm

In △ ABC, ab = AC angle bad = 20 ° and AE = ad angle CDE = ()
In △ ABC, ab = AC angle bad = 20 ° and AE = ad angle CDE = ()

What about the picture

Zhejiang Education Press eighth grade mathematics volume I exercise book (2) 2.1 isosceles triangle

1. B 2. 3 △ ABC △ ADC △ abd 3. Let the bottom of an isosceles triangle be x, and get 3x + X + 3x = 35, x = 5 3 * 5 = 15cm

The length of the bottom edge of an isosceles triangle is 10 cm. The middle line of the waist is drawn from one end of the bottom edge. The circumference of the triangle is divided into two parts. If one part is 4 cm longer than the other part, the waist length of the isosceles triangle is 0______ cm．

According to the meaning of the question, let the waist length of an isosceles triangle be x cm. There are two cases: when the upper part is smaller than the lower part, list the equation: 10 + x2 + 4 = 3x2, the solution is x = 14; when the upper part is larger than the lower part, list the equation: 10 + x2 = 3x2 + 4, the solution is x = 6, then the waist length of the isosceles triangle is 6 or 14cm

Ask the answer to the exercise
Name of exercise: Class:
1、 There are 6 sub questions in the main question, 3 points for each sub question, 18 points in total)
1. The diagonal length of a square with side length 1 is ()
A. Integer B. fraction C. rational number D. not rational number
2. The irrational numbers in the following numbers are ()
-0.333… ,,,,3 ,3.1415,2.010101… There is a 0 between two adjacent ones (the decimal part consists of successive positive integers). A.3 b.4 C.5 d.6
3. The following statement is correct: A. rational number is only a finite decimal; B. irrational number is an infinite decimal
C. An infinite decimal is an irrational number. D. is a fraction
4. The following statement is wrong: the square root of () a.1 is 1. B. – the cube root of 1 is - 1
C. Is the square root of 2 d. – 3 is the square root of 2
5. If the specified error is less than 1, the estimated value is ()
A. 3 B.7 c.8 d.7 or 8
6. In the following square roots, the simplified one is ()
A.B.C.D.
2、 Fill in the blanks (6 sub questions in total, 3 points for each sub question, 18 points in total)
7. Fill the following numbers in the corresponding set: - 7,0.32,46,0, -
① Set of rational numbers: { }(2) irrational number set: { };
③ Set of positive real numbers: { }Real number set: { }.
The arithmetic square root of 8.9 is, the square root of 3 is, the square root of 0 is, and the square root of - 2 is
9. – the cube root of 1 is, the cube root of 9 is
The opposite of 10 is, the reciprocal is, the absolute value of - is
11. Comparison size:;; 2.35. (fill in ">" or“

1D, 2a, 3C, 4 answers have questions, 5 questions can not be seen. 6 questions have no options
I can't stand it any more

1. If the square root of 2a-1 is ± 3, then a=------
2. √ (3.14 - π) & sup2; (calculation)
3. Given that the integer part of √ 21 is a and the decimal part is B, find the value of a & sup2; - B & sup2

1. Because the square root of 9 is ± 3, 2a-1 = 9, a = 52. π = 3.141592. π is greater than 3.14. Because 3.14 - π is less than 0, the square is first squared, so it is: π - 3.143. Because √ 21 is between √ 25 and √ 16, the integer part is 4, so the decimal part is √ 21-4, so a & sup2; - B & sup2; = 16 - (...)

Real test questions for Grade 8
Do you have any practical problems

Any rational number can be__________ Decimal or__________ The form of a decimal; 2____________ (3) real numbers include___________ And___________ (4) get the number from 0.07095 to 0.0001___________ And then it has_____________ One

Mathematics test paper (2) class____ Student number_ Name Total score_ 1、 The result of calculating (x-3y) (x + 3Y) is () a.b.c.d.3. It is known that the function value of the positive proportional function increases with the increase of, then the image of the first-order function is () 4. After the image of the first-order function y = x is shifted down two unit lengths, the corresponding function relation is () A. C.c.d.5. If and are of the same kind, then () a.b.c.d.6. A first-order function, after (1,1), (2,), then the value of K and B is () a.b.c.d.7. In the following patterns, there are () a.1 B.2 C.3 D.4 8 which are both axisymmetric and centrosymmetric. As shown in the figure, in △ ABC, ab = AC, D, E on BC, BD = CE, the logarithm of congruent triangles in the figure is () A. 0 B.1 C.2 d.39. When the following conditions are met, the congruence between △ ABC and △ def can be determined as follows: a. ∠ a = e, ab = EF, ∠ B = D; b.ab = De, BC = EF, ∠ C = f; c.ab = De, BC = EF, ∠ a = E; D. ∠ a = D, ab = De, ∠ B = E10, Suppose that the water level of the reservoir rises at a constant speed, then in the following images, what can correctly reflect the change of water level H (m) with time t (day) in these 10 days is () 2. Fill in the blanks (2 points for each question, 18 points in total) 1. Given point a (L), if two points a and B are symmetrical about X axis, then B If the point (3, n) is on the image of the function, then n =_ . 2. Calculation:;. 3. If the polynomial is a complete square, then. 4. If AB = 3, then. 5. Directly write the result of factorization: (1) as shown in the figure, in △ ABC, ab = AC, point D is on AC, and BD = BC = ad, then. 7. Line AB = 4cm, P is a point on the vertical of AB, and PA = 4cm, then ∠ APB=_ 8. In the activity of "new curriculum innovation forum", 60 "new curriculum innovation papers" collected in a city were evaluated and graded into five groups. The frequency distribution histogram as shown in the figure was drawn. According to the histogram, the excellent papers in this evaluation are as follows_____ 9. As shown in the picture, push and pull a rectangle (to the left and right)

Who has taught the eighth grade first volume mathematics midterm paper of the press? Send it