Square / 3 coefficient of 2 * 3.14 * H: Times:

Square / 3 coefficient of 2 * 3.14 * H: Times:

Coefficient = (2 × 3.14) △ 3 = 157 / 75
Times = 2
~I wish you progress in your study~~~
~If you agree with my answer, please click the "adopt as satisfactory answer" button in time~
~The mobile phone questioner can click "satisfied" in the upper right corner of the client
~Your adoption is my driving force~~
~If you have any new questions, please ask me for help. The answer is not easy. Please understand~~

How many meters is a square meter

Square meter is the unit of area, meter is the unit of length
The two cannot be converted

(1) The first figure (square) needs four sticks, the second figure needs seven sticks, and the eighth figure needs how many sticks?
(2) What is the fourth figure with 46 sticks
fast

Analysis: a square needs 4, two squares need 7, and three squares need 10. It can be seen that every square needs 3 sticks, so the relationship between the number of squares and sticks is 1 + 3N (n means the number of squares)
The number of sticks needed for the eighth figure of pendulum is: 1 + 3 × 8 = 25
With 46 sticks, it is: (46-1) △ 3 = 15 (figures)

How many squares can 157 sticks be placed? How many squares can 157 sticks be placed? How many equations

3n+1=157
3n=156
n=52
157 sticks can be placed into 52 squares

A small stick (Fig. 2, FIG. 4) with the same length is needed to form a pattern,
How many sticks does the pattern (n) need

Analysis: by observing the pattern, we can see that each next pattern has six more sticks than the previous one, and we can find the connection between 6 and N. as shown in the figure, the latter one always has two more rhombs than the previous one, and six more sticks,
The pattern (1) needs sticks: 6 × 1-2 = 4 (pieces),
Pattern (2) needs sticks: 6 × 2-2 = 10 (pieces),
Then the nth pattern needs sticks: (6n-2)
So the answer is: 6n-2

Use a stick to swing the figure below. Figure 1 needs three sticks, and Figure 2 needs seven sticks. According to this rule, the nth figure needs -- a stick?
It's a triangle. It's a combination

n(n+1)+1

The sum of two numbers equals 5, and the sum of squares equals 13. Why 2, 3,

Let one of the numbers be x and the other be 5-x
So x ^ 2 + (5-x) ^ 2 = 13
namely
2x^2-10x+12=0
namely
x^2-5x+6=0
namely
(x-2)(x-3)=0
So x = 2 or 3
So the other number is 3 or 2
So the answer is: one is 2, the other is 3

If the sum of the squares of a number and its half equals 5, then the number is ()
A. 2B. - 2C. 2 or - 2D. None of the above is true

Let this number be x, then x2 + (12x) 2 = 5, the solution is x = ± 2, so C

How can four numbers equal 13

5*（4-2）+3=13

The system of equations x + 3Y = 3 / 5 5 (x-2y) = - 4 is solved by proper method

x+3y=3/5 #1
5(x-2y)=-4 #2
Multiply both sides of # 1 by 5 to get 5 (x + 3Y) = 3 # 3
Subtract # 2 from # 3 to get 25y = 7 and y = 7 / 25
Take y into any # 1 or # 2 to get x = - 6 / 25