There are 100 peach trees in an orchard, each of which bears 1000 peaches on average. Now we are preparing to increase the yield by planting more than one tree. Without planting more than one tree, the yield of each tree will be reduced by 2. However, the number of peach trees should not exceed 100. If we want to increase the yield by 15.2%, how many trees should be planted? My method is to set up multiple x trees and get (100 + x) (1000x-2x) = 100000 (1 + 15.2%) Look at how wrong I am. If it's right, help me figure it out. If it's wrong, help me change it! How do you solve the equation

The one upstairs is wrong. He didn't learn it well. For every variety of trees, there are two less. For every x tree, there are 2x less. It should be (100 + x) (1000-2x) = 100 * 1000 (1 + 15.2%). It's not difficult to solve this problem. If you multiply it all, it's the one variable quadratic equation 100000-200x + 1000x-2x & sup2; = 115200x & sup2; - 400X + 76

Two practical problems of solving quadratic equation with one variable in the third grade of junior high school
1. A 90cm long, 40cm wide landscape painting is surrounded by a gold paper edge with the same width to make a wall map. If the area of the landscape painting is required to be 72% of the whole wall map area, what is the width of the gold edge?
2. A mirror is made by inlaying a frame with the same perimeter around a rectangular mirror glass. The ratio of length to width of the mirror is 2:1. It is known that the price of the mirror glass is 120 yuan per square meter, and the price of the frame is 30 yuan per meter. In addition, the processing cost of the mirror is 45 yuan. If it costs 195 yuan to make the mirror, the length and width of the mirror should be calculated
Just list the formula. If you are in a hurry, please let me know the final result

1. If the width of Phnom Penh is xcm, then
90*40*72%=(90+x)(40+x)
2. If the length of the mirror is 2XM and the width is XM, then
2x*x*120+30*2(2x+x)+45=195

A number divided by 11, the remainder of 8, divided by 13, the remainder of 10, divided by 17, the remainder of 14, this number is at least how small, ask God for help

If the number is increased by 3, then the number is exactly the common multiple of 11, 13 and 17. The minimum is to find the minimum common multiple. The minimum common multiple of 11, 13 and 17 is 11 × 13 × 17 = 2431, so the original minimum is 2431-3 = 2428

Sum of sequence: 1 * 4 + 2 * 7 + 3 * 10 +. + n (3N + 1)

N (3N + 1) = 3N ^ 2 + N, the whole sequence is divided into 3 (n ^ 2 + --- + 1 ^ 2) + N + (n-1) + --- + 1, and then directly set the formula

How many quarters are there in 1.25, and how many sixteenth are equal to 0.75

1.25 △ 0.25 = 5, there are 5 1 / 4
0.75 △ 1 / 16 = 12, 12 1 / 16 equal to 0.75

When m = - 3, n = - 2, what is the square of the algebraic formula m-2n

m²—2n²
=m²—n²—n²
=（m—2n)×（m+2n）—n²
When m = - 3, n = - 2, we substitute: {- 3-2 × (- 2)} × {- 3 + 2 × (- 2)} - (- 2) ² = 3
Hope to help you!

5 / 12-3 / 4 + 1.9 = what is it?

5 / 12-3 / 4 + 1.9
=5/12-9/12+19/10
=19/10-(9/12-5/12)
19/10-1/3
=57/30-10/30
=47/30

When k is the value, the solutions of the binary linear equations 5x + 4Y = 2K + 1, 2x + 3Y = 2, x > 0 and y = 1, x + 4Y = 2, x + 4Y = 2, x > 0 and y = 2, x + 4Y = 2, x + 4Y = 2, x + 4Y = 2, x + 4Y = 2, x + 4Y
It's not the coordinates of K, it's the value of K

First, according to the equations, we solve x, y (expressed by K)
It's easy: x = (6k-5) / 7
y=(8-4k)/7
If x > 0, k > 6 / 5
y2
So in the end, k > 2
The value of K is not definite, it is in a range

19 199 1999 19999.199.99 (after 999 9)

999 + 1 power of 10 * 2-1 the nth power of the nth number of 10 * 2-1

Proof: can the 53rd power of 53 - the 33rd power of 33 be divisible by 20?
I have a point of view to see if it's the same as what I think

Yes! In the n-th power of a minus the m-th power of B, there is a factor (a-b) after factoring this formula. For example: A ^ 2-B ^ 2 = (a-b) (a + b). A ^ 3-B ^ 3 = (a-b) (a ^ 2 + ab-b ^ 2). So 53-33 = 20 is OK