Solution: 7.5 times = 70+7 times
7.5X-7X=70
0.5X=70
X= 140
2. 16.5+8.7 = 25.2m，
2x16.5 = 33m
(25.2+ 16.5)x33/2=688.05[ m2]
688.05x9.5=6536.475
Answer; This land can receive 6536.475 kilograms of Robb.
this
The math moving point problem in senior one is urgent ~ ~ ~ ~ ~1. As shown in the figure, the side length of the square ABCD is 5cm, at Rt△EFG, ∠ G = 90, FG = 4cm, EG = 3cm, and points B, F, C and G are at.
(1) When △EFG moves, find the time when point E moves to CD and AB respectively;
(2) After setting x (seconds), find the area of the overlapping part of △EFG and square ABCD as y(cm), and find the functional relationship between y and x;
(3) Draw an approximate image of the function in (2) when 0≤x≤2 in the following rectangular coordinate system; If the circle centered on O intersects with the image at point P (x,) and the X axis intersects at point A and point B (A is on the left side of B), find the number of times ∠PAB.
2. As shown in the figure, in the right-angled trapezoid COAB CB‖OA, the plane rectangular coordinate system is established with O as the origin, and the coordinates of A, B and C are A (10/0,0), B (4 4,8), C (0 0,8), D is the midpoint of OA, and the moving point P is from point A.
(1) When the moving point P moves from A to B, let the area of △APD be S, try to write the functional relationship between S and T, point out the range of independent variables, and find the maximum value of S.
(2) Starting from the moving point P, a few seconds later, the line segment PD divides the area of the trapezoidal COAB into two parts: 1: 3? Find the coordinates of point p at this time.
3. As shown in the figure, in the plane rectangular coordinate system, the quadrilateral OABC is rectangular, and the coordinates of point A and point B are (3,0) and (3,4) respectively. Moving points M and N start from O and B at the same time, respectively, and move at the speed of 1 unit per second. Among them, point M moves to endpoint A along OA, and point N moves to endpoint C along BC ... Through point N as NP⊥AC, it crosses AC to P and connects MP. It is known that the moving point has moved for x seconds.
The coordinate of point (1)P is (,); (represented by an algebraic expression containing x)
(2) Find the maximum value of ⊿MPA area and the value of X at this time.
(3) Please explore: When X is what value, ⊿MPA is an isosceles triangle? How many situations have you found? Write your research results.
4. As shown in the figure, in the middle, 0,0 cm, the particle P moves at a uniform speed along a straight line from point A, and the particle Q moves at a uniform speed along a straight line from point D, the midpoint of AC, and gradually approaches the particle P. Let the velocities of the two particles P and Q be 1 cm/s and cm/s () respectively, and meet at a certain point E on the BC side one second later. (1) Find the length of AC and BC; (2) Will the point E where two particles meet be the midpoint of BC? Why? (3) If the triangle with vertices d, e and c is similar to △ABC, try to sum the values respectively;
5. In the triangle ABC, the existing moving point P starts from point A and moves in the direction of point B along ray AB; Moving point q starts from point c and moves in the direction of point b along ray CB. If the speed of point P is/sec and the speed of point Q is/sec, they start at the same time. Found: (1) After a few seconds, is the area of Δ δPBQ half that of ABC? (2) On the premise of (1), what is the distance between P and Q?
6. As shown in the figure, in the known right-angled trapezoidal ABCD, AD‖BC, ∠A=90o, ∠C=60o, AD=3cm, BC = 9cm. ⊙ O 1 Start from point A and follow the A-D-C polyline.
(1) Find the value of t when ⊙O2 is tangent to waist CD;
(2) In 0s
7. As shown in the figure, it is known that the lengths of trapezoid AOBC(O is the origin), AC‖OB, OC⊥BC, AC and OB in rectangular coordinate system are the two roots of the equation x2-(k+2) x+5 = 0, S △ AOC: S △ BOC = 1.
(1) Fill in the blanks: 0c = _ _ _ _ _ _ _ and k = _ _ _ _ _ _ _
(2) Find another intersection of parabola through O, C and B. Moving points P and Q start from O and D at the same time, and both move at the speed of 1 unit per second, where point P moves from O to B along o B, point Q moves from D to C along DC, and the intersection point Q makes QM⊥CD pass through BC at point M, connecting △PMB and B.
How to solve x-3 2x=42? Urgent. . . . . . . . . . Solution: x-3 2x=42
1x=42。
x=42×3
x= 126
Senior one, basically unequal, urgent! 92V & gtV^2+3V+ 1600
v^2-89v+ 1600<； 0
(v-44.5)^2<； 380.25= 19.5^2
- 19.5 & lt； v-44.5 & lt； 19.5
25 & ltV & lt64
Sixth grade math problem, (⊙ o ⊙) Ah! Emergency judgment
1. The railway from Beijing to Shanghai is about 1463 meters long. (Wrong) It should be "kilometers"
2.a×2 is greater than A (error)
3.a+(b-c)=a-b+c (wrong) should be: A+B-C.
In the first quarter of this year, there were 9 1 day (wrong, February was not considered)
5.2 1 ton is 50% ton (right).
Shift+Delete to get back ~ ~ ~! ! ! ! Urgently ... ask the master for help. ! ! ! ! Try another software. This has nothing to do with time. Mainly depends on whether the original partition slot has written data.
Click my name, and then click "His Space". My space has a detailed introduction of various recovery software, as well as instructions and registration codes. You can go and have a look. I recommend you to try the data recovery software of SuperRecovery super hard disk. This is the best recovery tool at present. If this doesn't work, there may be no way out.
Urgent! A mathematical geometry problem. Quick solution for connecting EF
Then ∠ g = 180-∠ GFE-∠ GEF.
= 180-(∠GFA+∠AFE)-(∠GEA+∠AEF)
= 180-(∠AEF+∠AFE)-(∠GEA+∠GFA)
= 180-( 180-∠FAE)- 1/2(∠AEC+∠AFC)
=∠FAE- 1/2(∠AEC+∠AFC)
=∠da B- 1/2( 180-60-∠C+ 180-80-∠C)
=∠da B- 1/2( 120-2∠C+ 100)
=∠DAB+∠C- 1 10
=(360 -60 -80 )- 1 10
= 1 10
JAVA programming a simple JAVA problem is urgent! Give it to me! east
60th anniversary of People's Republic of China (PRC) and 60th anniversary of People's Republic of China (PRC).
60 years can be said to be a snap of your fingers! 60 years of personal experience has touched the pulse of social progress, and 60 years of reform and opening up have benefited everyone in China.
197865438+February, the Third Plenary Session of the Eleventh Central Committee of the Party was successfully held, which opened a new historical period of reform and opening up and was a great turning point with far-reaching significance in the history of our party since the founding of the People's Republic of China.
The national economy has developed rapidly in the past 30 years, and our living and working conditions have also changed greatly in these 30 years. Food, clothing, housing and transportation, living environment and working conditions are all earth-shaking.
According to my mother, in the era of voucher supply during the planned economy period, you can buy at most two new clothes a year, or ordinary plain cloth. The expectation of "wearing new clothes for the New Year" was the wish of peers at that time. If you can put on new clothes before the New Year, the satisfaction and pride envied by your neighbors are beyond the reach of young people nowadays, not to mention that every little angel now has at least several sets of clothes with good styles and textures and distinct seasons.
The supply of food is unforgettable for my mother. It is natural to buy meat with tickets, but there is absolutely no need to be picky, let alone wait in line in the crowded open air and worry about whether it is my turn to buy goods. Because of the scramble for food, adults make noise and even scramble for food, which scares children. When my mother was a teenager, she was most afraid of letting her parents shout in line. When accepting this task, she often insisted that "I would rather not eat meat than wait in line". In the sixties and seventies, materials were extremely scarce. A piece of brown sugar or tofu, or even Chili noodles with some salt, was once a common snack for people. At that time, eating with relish was no less than the excitement of children eating the latest food on the market, and the carefree after being numb by peppers was no less than the hearty after eating hot pot.
Thirty years ago, many families had only one house. Almost the same layout is to put a bed or a wardrobe in the middle of the house, draw curtains and divide the house into two rooms, with the living room and dining room in front. My mother said that when they play, they can only sit under the covers. If conditions are better, they can prepare one or two ponies or Xiao Mu stools. Families with many children have to be designed as bunk beds, with another bedroom and storage room behind the bed. When conditions are good now, most people live in three rooms and one living room and have their own independent kingdom. That kind of excitement is self-evident.
Not to mention how advanced the automation office conditions are now, I don't know how many kinds of water heaters have been changed just by drinking boiled water. In the late 1950s, boiling water could only be prepared during the supply time of the boiler room in the morning to ensure the needs of the whole day. It's uncomfortable to sit next to the office and reach out and add pure water to the water dispenser now.
Communication tools have also changed. In the 1980 s, a hand-held telephone was used, and it was a headache every time you needed to contact, not to mention connecting the operator of the post office first and then transferring to a certain place or unit. If the other party's signal is not very good, you have to make several calls, and sometimes it takes even a day to get through. In the 1990 s, the pioneer of reform and opening up, wearing a BB around his waist, used paging signals to make calls at any time. Every time he makes a phone call, he even pretends not to hear it, so that the phone can ring a few more times ... The pride of the holder is self-evident. In the Millennium, mobile phones have once again become a status symbol. The holder should not only shout in a voice out of proportion to his height, but also speak in the local language to make him feel like a saint in front of others. In today's 2 1 century, everyone has more than one mobile phone in his hand, so wherever he goes, he is close at hand, and his work efficiency and economic benefits are fruitful.
I have been touched by the changes in the past 60 years, but what I have experienced is only a small microcosm of the lives of thousands of people in Qian Qian. In the past 30 years of reform and opening-up, China has gone through hundreds of years of history in western capitalist countries, and its great achievements have not come easily. We live in such a beautiful golden age, and this happy, stable and harmonious situation also needs us to cherish and maintain. Through our efforts and struggles, the motherland will become more and more prosperous and the people's lives will become better and better.
How to install sim card on iphone 4? Be specific. There is a small hole in it. Stick it with a toothpick and it will pop up. The card will be installed in it.