People's education printing plate eighth grade second volume mathematics final examination questions
A, multiple-choice questions (3 points per question, ***24 points):
The reciprocal of 1 and 2 is ()
a、2 B、2 C、D、
2. Among the following eligible triangles, the one that is not a right triangle is ().
A. The ratio of three internal angles is 1:2:3 b. The ratio of the squares of three sides is1:2: 3.
C. The ratio of three sides is 3:4:5 d. The ratio of three internal angles is 3: 4: 5.
3. If P(m+3, 2m+4) is on the Y axis, then the coordinate of point P is ().
A.(? 2，0) B.(0，？ 2) C.( 1，0) D.(0， 1)
4. Known straight line y = kx-4 (k
A.y=-2x-4 B.y=-x-4
C.y=-3x+4 D.y=-3x-4
The arithmetic square root of 5 and 4 is ()
a、2 B、 16 C、2 D 、? 16
6. The value of the sum in the equation solution is equal to ()
A.2 B.4 C.3 D. 1
7. The median and mode of a set of data 6, 8, 7, 8, 10, 9 are () respectively.
A7 and 8 B.8 and 7 C.8 and 8 D.8 and 9.
8. As shown in the figure, if ∨, the degree is ().
A.B. C. D。
Fill in the blanks. (3 points for each question, * * * 2 1 point)
9. The number of trees planted in six greening groups in a school is as follows: 10,1,12, 13, 8, X. If the average value of this set of data is 1 1,
10. In △ABC, AB= 13 cm, AC=20 cm, and the height of the side of BC is 12 cm, so the area of △ABC is _ _ _ _ _ _ _ _ _ _.
1 1. It is known that A and B are two consecutive integers, A >:& gt；; B, then a+b = _ _ _.
12 。 Let the real numbers x and y satisfy the equation, then x+y = _ _ _ _ _.
13. The coordinate of the intersection of the function and the image is _ _ _ _ _ _ _ _.
14.(20 12 Huaihua, Hunan, 16, 3 minutes) In a certain period of time, the daily maximum temperature measured by Xiao Ming for seven consecutive days is shown in the following table, so the average temperature of the maximum temperature for these seven days is _ _ _ _℃.
Temperature (℃) 26 27 25
Day 1 3 3
15.(20 12 Quanzhou, Fujian, 15,4) as shown in the figure, in △ABC,? A=60？ ,? B=40？ Point d and point e are on the extension lines of BC and AC respectively, then? 1= ______ 。
3. Answer the questions. (* * * 75 points)
16 calculation (4 points for each question, * * * 8 points)
( 1) [(3)2- ]? (-3) (2)
17( 10 minute) Solve the equation: (1); (2)
18.( 10 point) As shown in the following page, fold one side of the rectangular AD so that the D point falls on the F point on the side of BC, BC= 10 cm, AB=8 cm.
Find: the length of (1) fc; (2) the length of 2)EF.
19.(3) Establish an appropriate rectangular coordinate system in the map to represent the position of each scenic spot in the map. (3 points for establishing coordinate system and 3 points for point coordinate)
A Shihushan B Houshan C Rare Bird Pavilion D Panda Pavilion E Dashan F Playground G Corridor
20.( 10) It is known that y and x are linear functions. When x=0, y=3, when x=2, y=7.
(1) Write the functional relationship between y and x.
(2) Calculate the value of y when x=4.
(3) Calculate the value of x when y=4.
2 1(8 points). Known AC∨BD, CAE=30? ,? DBE=45, q? AEB degree
22 (10) Wang contracted two barren hills A and B a few years ago, and all kinds of Myrica rubra 100 plants, with a survival rate of 98%. Now it has blossomed and borne fruit, and the economic benefits have initially appeared. In order to analyze the harvest, he randomly picked four Myrica rubra trees from two mountains, and the output of each tree was shown on the statistical chart.
(1) Calculate the average values of samples from Mountain A and Mountain B respectively, and estimate the total output of Myrica rubra from Mountain A and Mountain B;
(2) Through calculation, which mountain has stable bayberry yield?
23.( 10) In order to encourage residents to save electricity, the city has implemented a ladder price for residents' electricity charges since 20 12, that is, the electricity consumption of each household is divided into three grades, and the first grade is the part with electricity consumption within 180 kWh (including 180 kWh), and the basic electricity price is implemented; The second gear is the part with electricity consumption ranging from 180 kWh to 450 kWh (including 450 kWh), and the electricity price will be raised; The third gear is the part where the electricity consumption exceeds 450 kWh, and the market-adjusted price is implemented. A classmate's home in our city used 330 kwh electricity in February this year, and the electricity fee was 2 13 yuan. In March, the electricity consumption was 240 degrees, and the electricity fee was 150 yuan. It is known that the household electricity consumption of a resident in our city in April and May this year was 160 and 465438+ respectively.
People's education printing plate eighth grade second volume mathematics final exam questions reference answer
First, multiple-choice questions: BDBA·ADCC
Two. Fill in the blanks 9.1210.1261.112.813.14.
3. Answer the questions. 16 problem (1) solution =(3-2)? (-3) (2) Solution =
=-3
Problem 17 (1) solution: x=2, y=- 1 (2) solution: x= 5, y=7.
18 solution: (1) From the meaning of the question, AF=AD=B C= 10 cm,
In Rt△ABF,? B=90？ ,
∵ cm，？ ，BF=6 cm，
? (cm). (2) from the meaning of the question, get and set the length as, then.
At rt delta? C=90？ ,
We can draw a conclusion from Pythagorean theorem,
The solution is 5 cm in length.
Introduction to 19
20 questions:
Solution: (1) Let the linear function relation be: y=kx+b (k? 0)
Then the solution of the equation is:
? The linear function is y=2x+3.
(2) When x=4, y=2? 4+3= 1 1
(3) when y=4, x=
2 1 Question: A: 75
Question 22: (1) =40 (kg),
=40 (kg),
The total output is 40? 100? 98%? 2=7840 (kg);
(2)= 14[(50-40)2+(36-40)2+(40-40)2+(34-40)2]= 38(kg ^ 2)，
= 14[(36-40)2+(40-40)2+(48-40)2+(36-40)2]= 24(kg 2)，
? & gt。
A: The yield of Myrica rubra in Mountain B is relatively stable.
Question 23: Solution: Set the basic electricity price as X yuan/kWh and increase the electricity price to Y yuan/kWh.
Judging from the meaning of the question:
180 x+ 150y = 2 13 180 x+60y = 150
Solution: x=0.6y=0.7.
? The electricity bill in April is: 160? 0.6=96 yuan
The electricity bill in May is: 180? 0.6+230? 0.7 =108+161= 269 yuan.
A: The electricity bills of this resident in April and May were 96 yuan and 269 yuan respectively.