The classroom (flat roof room) of the experimental primary school is 8 meters long, 6 meters wide and 4 meters high. The roof and four walls of the classroom should be painted, and the doors, windows and blackboard should be removed And the blackboard area is 25.4 square meters. How many square meters is the painting area?

The classroom (flat roof room) of the experimental primary school is 8 meters long, 6 meters wide and 4 meters high. The roof and four walls of the classroom should be painted, and the doors, windows and blackboard should be removed And the blackboard area is 25.4 square meters. How many square meters is the painting area?

Except that the floor does not need painting, the area of the wall and roof = L * W + (w * H + L * h) = 8 * 6 + (6 * 4 + 6 * 4) * 2 = 144
Area to be painted = 144-25.4 = 118.6m2

How much air conditioning power do you need to buy for a room of 50 square meters

It depends on the room's sealing and thermal insulation conditions and the number of personnel. If the conditions are good, three HP air conditioners with a cooling capacity of 7500w can be used (the cooling power is generally about 2200W). If the conditions are poor, four HP air conditioners with a cooling capacity of 10000w are best used (the power is about 3000W)

In a room of 50 square meters, how many air conditioners do you need to heat the room to 35 degrees?
The window area of the room is about 16 square meters and the height is 3 meters

Now the highest set temperature of air conditioner on the market is 30 degrees. To meet your requirements, I suggest you buy a 5-piece air conditioner, and redesign the circuit according to your needs

Two times the square of a number is equal to seven times the number. What is the number?

7 or 0

1. If the square of a number is equal to 4 / 9, then the number is () and the number whose value is 2 / 3 is ()
2. On the number axis, there are four points of unit length with the distance from point - 3, which are ()
3. The opposite number of - (+ 2) is (), (2-A) is the opposite number of ()
4. If | X-1 | + (y + 2) ^ 2 = 0, then (x + y) ^ 2011 = ()
5. If | A-B | = B-A, then the relationship between a and B is ()
6. If | a | = 2, B ^ 2 = 25, AB < 0, then a + B = (), | A-B | = ()
7. When B < 0, the order of a, A-B, a + B, a-2b is ()
[only write the result, not the formula]

1. If the square of a number is equal to 4 / 9, then the number is (± 2 / 3); if the absolute value is equal to 2 / 3, then the number is (± 2 / 3) 2. There are (2) points on the number axis whose distance from point-3 is four units of length, they are (- 5 or 1)
3. The opposite number of - (+ 2) is (2) and (2-A) is the opposite number of (A-2)
4. If | X-1 | + (y + 2) ^ 2 = 0, then (x + y) ^ 2011 = (- 1)
5. If | A-B | = B-A, then the relationship between a and B is (a ≤ b)
6. If | a | = 2, B ^ 2 = 25, AB < 0, then a + B = (± 3), | A-B | = (7)
7. When B < 0, the order of a, A-B, a + B, a-2b is (a + b)

If the difference between the square of a number and the number is equal to 0, then the number can only be ()
A. 0b. - 1C. 1D. 0 or 1

If the number whose square equals itself is 0 and 1, then the number is 0 or 1

How to subtract the square of one number from the square of another?

Generally, the square difference formula can be used to simplify the calculation of a ^ 2-B ^ 2 = (a + b) (a-b)

The square of a few is 144

.
twelve

Is there any square number in Fibonacci sequence besides 1 and 144?

There are many more, you can use the program to achieve, the following is the matlab program: function f = Fibonacci (n) Fibonacci = [1,1]; if n = = 1 Fibonacci = [1]; else if n = = 2 Fibonacci = [1,1]; else for II = 3: nfibonacci (II) = Fibonacci (II-1) + Fibonacci (II-2); e

Why is the square of 12 144
B sweat

12²=12*12=12*10+12*2=120+24=144