According to the structure of the bridge, which kind of bridge can be divided into

According to the structure of the bridge, which kind of bridge can be divided into

According to bridge structure classification:
1. Beam system, as a load-bearing structure, bears load with its bending capacity
2. Arch system, the main load-bearing structure is arch rib (or arch box), mainly bearing pressure. Arch is also divided into single hinge arch, double hinge arch, three hinge arch and no hinge arch. Arch is a thrust structure, which requires higher foundation
3. Rigid frame bridge system is a kind of system between beam and arch. It is an integral structure with upper bending and lower bearing. It is generally used for urban bridges or overpasses with small span
4. Suspension bridge system, with suspension as the main bearing structure, has large span, simple and clear force, light weight and weak wind resistance
5. Composite structure system, including continuous rigid frame, beam arch composite system (such as tied bridge, truss bridge), cable-stayed bridge system
I hope my answer can help you!

There are several books on each shelf. If you take 100 books from shelf B and put them on shelf a, the books on shelf a are five times more than those left on shelf B. If you take 100 books from shelf a and put them on shelf B, the books on both shelves are equal. How many books are there on each shelf?

Suppose there are x books on the first shelf, then "if you take 100 books from the second shelf and put them on the first shelf, then the books on the first shelf are five times more than the books left on the second shelf; if you take 100 books from the first shelf and put them on the second shelf, then the books on the two shelves are equal."
We can get x + 100 + (x + 100) / 6 = total number = 2 (X-100)
The result is 5x = 1900
x=380
B bookshelf can therefore be solved. This problem is best solved by binary linear equation
The number of books on shelf a is five times more than that on shelf B. the number of books on shelf a is six times more than that on shelf B

The distance between a and B is 135 kilometers. Two cars, big and small, drive from a to B. the big car starts 5 hours earlier than the small car, and the big car arrives 30 minutes earlier than the small car. The speed ratio of the small car to the big car is 5:2
I set the speed of the big car to be 2x and the speed of the small car to be 5x. Can you help me?

The bus starts 5 hours earlier and arrives 30 minutes earlier, which means 4.5 hours more
Therefore:
135/2x - 135/5x =4.5
The solution is: x = 9
Therefore, it is 18km / h for large cars and 45km / h for small cars
Tell your teacher, there is something wrong with this question. Normally, no one drives so slowly

In the plane rectangular coordinate system, as shown in Fig. 1, the line AB is translated to the line CD, connecting AC, BD (2) with known a (- 3,0), B (- 2,2)
 
In the plane rectangular coordinate system, as shown in Figure 1, translate the line AB to the line CD, and connect AC and BD. & nbsp;
 
(1) Directly write out the equal and parallel line segments in the graph;
 
&(2) given a (- 3,0), B (- 2,2), point C is on the positive half axis of y-axis, point D is in the first quadrant, and s triangle ACD = 5, find the coordinates of point C
 
(3) In the plane rectangular coordinate system, as shown in Figure 2, a certain point m (1,0), two moving points e (a, 2A + 1), f (B, B + 5) are known. Please explore whether there is a line segment EF with two moving points e, F as endpoints, which is parallel to and equal to the line segment OM. If there is, find the area of the quadrilateral with points o, m, e, F as vertices. If not, please explain the reason;
 
There are no correct answers everywhere on Baidu, so don't fool me with copy and paste~
The first question is that I have made it myself, but the second question and the third question have no clue,
 
Figure 1
B is (- 2, - 2)
The graph just shows the general quadrant of the point!

(1) According to the nature of translation, if AB / / CD and ab = CD, then the quadrilateral ABCD is a parallelogram, х AD / / BC and ad = BC. х X09 (2) we know a (- 3,0), B (- 2, - 2), let the analytic expression of the line AB be y = ax + B, then there are 0 = - 3A + B, - 2 = - 2A + B, then the solution of the line AB is a = - 2, B = - 6

There are four cases of apples with the same weight. After taking 24 kg from each case, the sum of the weight of the remaining apples in each case is the same as that of the original case. How many kg does each case weigh?

Set x kg for each box of apples
The result is: 4x-24 = 2x
2x=24
x=12
A: it used to weigh 12 kg
Ask me if you don't understand

（3a-2b-C）^（2）

(3a-2b-C)²
= 9a² - 6ab -3ac - 6ab +4b² +2bc - 3ac +2bc +c²
=9a² +4b² +c²- 12ab -6ac +4bc

A batch of fruit was delivered to the fruit shop. It is known that there are 100 kg apples and 8 kg pears more than 1 / 4 of the total number of fruits. Apples and pears account for 5 / 12 of this batch of fruits
How many kilos of fruit are there altogether?

(100 + 8) / (5 / 12-1 / 4) = 648kg
Equation:
Let's suppose that the fruit is x kg in total
100+1/4x+8=5/12x
1/6x=108
x=648
A: there are 648 kilograms of these fruits

What is (2 ^ 1 + 1) (2 ^ 2 + 1) (2 ^ 4 + 1) (2 ^ 8 + 1) (2 ^ 16 + 1) (2 ^ 32 + 1) (2 ^ 64 + 1) equal to?

Idea: multiply (2-1) by the original formula to produce square difference, which can be solved skillfully. (2 ^ 1 + 1) (2 ^ 2 + 1) (2 ^ 4 + 1) (2 ^ 8 + 1) (2 ^ 16 + 1) (2 ^ 32 + 1) (2 ^ 64 + 1) original formula = (2-1) (2 ^ 1 + 1) (2 ^ 2 + 1) (2 ^ 4 + 1) (2 ^ 8 + 1) (2 ^ 16 + 1) (2 ^ 32 + 1) (2 ^ 64 + 1) = (2 ^ 2-1) (2 ^ 2 + 1) (2 ^ 4 + 1) (2 ^ 8 + 1) (2 ^ 16

The effective value of the two positive and negative AC currents I1 and I2 is I1 = I2 = 4A. When the effective value of the total current is 4a, what is the phase difference between them?

It's 120 degrees

Xiaoliang is 12 cm higher than Xiaoqiang, Xiaogang is 4 cm higher than Xiaoliang, Xiaogang is 136 cm tall, how many meters is Xiaoqiang?
We need formulas, not equations!

136-4-12 = 120 (CM) = 1.2 (m)