An isosceles triangle flower bed is 25 meters long at the bottom and 20 meters long at the waist. How long does it take to build a fence around the flower bed

An isosceles triangle flower bed is 25 meters long at the bottom and 20 meters long at the waist. How long does it take to build a fence around the flower bed

20x2+25=65

A rectangular flower garden, its area is 30.8 square meters. The length of the flower garden is 11 meters. Now we need to fence around it. How long is the fence?

Width 30.8 △ 11 = 2.8m
Fence length (11 + 2.8) × 2 = 27.6m

There is a rectangular flower garden, 18 meters long and 8 meters long. How many square meters is the area of this flower garden? How long is the fence around the flower garden

1. The area is 18 * 8 = 144 square meters;
2. Fence length (18 + 8) * 2 = 52m

The definition field of function f (x) is d = {x | x ≠ 0}, and f (x1 &; x2) = f (x1) + F (x2) for any x1, X2 ∈ D
The definition field of function f (x) is d = {x | x ≠ 0}, and f (x1 &; x2) = f (x1) + (x2) for any x1, X2 ∈ D
If f (4) = 1, f (x-1) < 2, and f (x) is an increasing function on (0, + ∞), the value range of X is obtained
If f (x) is an even function and f (x-1) < 2, then f (| X-1 |) < f (16) is obtained, and because f (x) is an increasing function on (0, + ∞)
So 0 ＜ X-1 ＜ 16
The solution is - 15 < x < 17 and X ≠ 1
Doubt: how to get the absolute value? What's the basis? Why x ≠ 1? I've been thinking about these two questions all afternoon. Thank you very much

Please refer to the figure below:

It is known that the image of a function y = KX + B passes through point a (0,1) and point B (a, - 3a) (a)

The image of a linear function y = KX + B passes through points a (0,1) and B (a, - 3a) (a)

The diagonal of the rectangle is 10cm, the area is 25 and the root is 3cm2, so what is the acute angle between the two diagonals? Why?

60 ° this is the simplest solution to the quadratic equation of two variables. You can set the length of both sides of the rectangle as a and B, so that a ^ 2 + B ^ 2 = 10 ^ 2, ab = 25 and root 3. You can find a and B, but after a long time, you can see that the rectangle with 1 and root 3 on both sides has a diagonal of 2 and an area of root 3, which is only multiplied by 5
Common triangles, rectangles, such as this, the rule that the angle between the edge and the diagonal is 30 ° is best remembered

If 6x-3y = 16, 5x + 3Y = 16, then 4x-3y =?
This is a math problem,

This is to solve the equation directly
We can get x = 32 / 11, y = 16 / 33
Substituting 4x-3y, the solution is 112 / 11

Using three different methods to solve the equation 3x & # 178; - 5x = 2

3x^2-5x=2
3x^2-5x-2=0
The first method is as follows
Δ=(-5)^2-4×3×(-2)
=25+24
=49
x=(5±√49)/6
=(5±7)/6
x1=(5-7)/6=-1/3
x2=(5+7)/6=2
It can be divided into two parts
(3x+1)(x-2)=0
3x+1=0
x=-1/3
Or X-2 = 0
x=2
It can be divided into three parts
3[x^2-5/3x+(5/6)^2]=2+3×(5/6)^2
3(x-5/6)^2=49/12
(x-5/6)^2=49/36
x-5/6=±7/6
x=(5±7)/6
x1=(5-7)/6=-1/3
x2=(5+7)/6=2

If the slope of AB is known to be 1, then the equation of line L is (complete process)

Such as (1) 1! + 2! + 3! + +The number of n! (n is greater than or equal to 4, n belongs to a positive integer) is ------ (answer: 3);

1!+2!+3!+4!=1+2+6+24=33
n> 4, n! Can be divided by 2,5, that is, n! Is 0, so the sum of n! Is 3