How many jin is one liter of water?

How many jin is one liter of water?

two

How many grams of water is two liters of water?

The density of water is 1 gram per cubic centimeter, 2 liters equals 2000 cubic centimetres, so it's 2000 grams

If the three sides of a triangle are a, B, C and satisfy A4 + B4 + C4 = a2b2 + b2c2 + c2a2, the triangle is equilateral

A 4 + B 4 + C 4 = A 2B 2 + B 2C 2 + C 2A 2, the left and right sides of a 4 + B 4 + C 4 = A 2B 2 + B 2C 2 + C 2A 2 are all × 2, which is written in the form of complete square: (a 2-B 2) 2 + (b 2-C 2) 2 + (C 2-A 2) 2 = 0, ∵ a, B, C are the three sides of the triangle respectively, ∵ a, B, C are nonnegative, ∵ a 2-B 2 = 0, B 2-C 2 = 0, C 2-A 2 = B 2, C 2 = a 2 ∵ a = b = C, the triangle is equilateral triangle

Choose 9 numbers from 1 to 9 (repeatable), and the sum is equal to 55. Is there a formula to calculate?
Thank you for listening to the wind on the screen, but do you have any specific formula or technique?

Yes,
Obviously, the number of [9-81] can be obtained by adding 9 numbers between 1-9
1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 9 is the template,
When the components of 55-9 = 46 are allocated to the positions of 1, each allocation method can get different addition methods, such as
Try to average 6 + 6 + 6 + 6 + 6 + 6 + 6 + 6 + 6 + 6 + 7 = 55,
Try to add odd number 1 + 3 + 5 + 7 + 9 + 7 + 7 + 7 + 9 = 55,
Try to add even number 2 + 4 + 6 + 8 + 8 + 8 + 8 + 8 + 3 = 55,

Solve the equations 4x-3y = - 4.2 X-Y = 2
There should be a process

4x-3y=-4 ①
x/2-y=2 ②
① - 2 * 8
5y=-20
y=-4
Substituting in (2)
x/2-(-4)=2
x/2=-2
x=-4
So x = - 4, y = - 4

Simple calculation of 17 times 5 of 9 and 19
Simple calculation
(1) Nine and nineteen seventeen times five
(2) 14 out of 99 and 25 times minus 5
And tell me why

The first, (10-2 / 19) X5 = 50-10 / 19 = 49 + 9 / 19
The second, (100-11 / 25) x (- 5) is the same as above
There's no reason. It's just like this. It's easy to make up a good number

3 ^ 2-1 ^ 2 = 8 * 1 5 ^ 2-3 ^ 2 = 8 * 2 7 ^ 2-5 ^ 2 = 8 * 3. Question: 1. What law do you find from the above equation? Express it in algebraic form
2. Calculate from the above rule: 2001 ^ 2-1999 ^ 2

(2n+1)^2-(2n-1)^2=8n
Simplify the formula on the left, as follows
(2n+1)^2-(2n-1)^2＝4n^2+4n+1-4n^2+4n-1=8n

(35-12 / 6, 49 + 63-30 / 20, 77 + 91-56 / 42, 105) - 1 and 3 / 8] divided by 1 / 8

[(35-12 / 6, 49 + 20, 63-30, 77 + 42, 91-56, 105) - 1 and 3 / 8] / 1 / 8
=[6-1 / 6-4-1 / 12 + 3 + 3 / 20-2-17 / 30 + 2 + 1 / 6-2-1 / 8-1 and 1 / 8] × 8
=【2-1/12+3/20-17/30-1/4】×8
=5/4×8
=10

For a triangle, if the base increases by 2 cm, the height remains unchanged, and the area increases by 12 square cm; if the height decreases by 3 cm, the base remains unchanged, and the area decreases by 12 square cm

Let the height of the original triangle be h cm and the bottom be a cm, (a + 2) × h △ 2-ah △ 2 = 12 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 2H = 12 × 2 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp

Solving equation 36 + x-2x = 18

36－x＝18