Math Problems As long as the arithmetic method is used, the math is calculated by the problem

The ** line assigned to three workers is also x meters long.

Since the first worker divided the total length of 1, 4 more than 20 meters.

So the full field of the ** line is 4 (x-20) meters.

The second worker was assigned the ** line length is.

4(x-20)-x]/4 + 40

According to the title, there is [4(x-20)-x] 4 + 40 = x to get x = 80

So the total length is 4 (80-20) = 240 meters.

Solution: Counting from the third person, because the wires are divided, so.

To the third person divided the remaining 1 4 more than 60 meters, which is more.

60 meters is the remaining 3 4, otherwise, there will be no end of points.

Then it's easy to do, and the remaining length is when it comes to three people.

60 (3 4) = 80 meters, which is also the length of the third person.

Because the three of them share the same amount, they are always long.

80*3 = 240 meters.

Let the total length be l, and the workers will be assigned A, B, and C respectively

a=1/4l+20 (1)

b=(l-a)/4+40 (2)

c=(l-a-b)/4+60(3)

a=b=c (4)

From (1), (2), (4), 1 4l = 60

l = 240** total length 240 m.

The same can be derived.

Substituting (1) yields a=80

It can be seen from (4).

a=b=c=80

The two above said that it is arithmetic, not liberation. Ay.

Ignorant little children ... Alas.

Computer -- Run -- Enter calc --- computer -- do the calculations yourself.

Hello The answers are: And.

First of all, your first question is that your calculations are exactly correct and there are no mistakes.

Your second question I'm doing this to you. From (2x+5y)-(2x+3y) to (2x-2x)+(5y-3y), it has two knowledge points, one is the knowledge point of brackets, and the main point of brackets is that if the symbol before the formula in the parentheses is a plus sign, the sign before the formula in the brackets will remain unchanged, otherwise, if it is a negative sign, it is necessary to change the sign (that is, the plus sign becomes a minus sign, and the minus sign becomes a plus sign). Therefore, (2x+5y)-(2x+3y) to remove the parentheses is 2x+5y-2x-3y, and then we use the method of moving terms to merge similar terms to convert them into 2x-2x+5y-3y.

Because as I said earlier, the subsign of the formula after the plus sign does not change. And these two knowledge points are about algebraic formulas.

From the binary equation, you are using the elimination method. Then if you can write it, you must know how to use the elimination method for this problem. In fact, it is to eliminate the same unknown, and then find another unknown, and finally according to the unknown to find the eliminated unknown.

It doesn't matter which formula is minus which formula. Because some people are used to having positive numbers on both sides of the equation, while some people feel that it doesn't matter if there are negative numbers.

8/7 + 9 + 10) = 3 + 6 7

9/8 + 10 + 11) = 3 + 6 8

10 + 11 + 12) = 3 + 6 9

11/10 + 12 + 13) = 3 + 6 8/107 + 9 + 10) - (9/8 + 10 + 11) + (10/9 + 11 + 12) - (11/10 + 12 + 13).

—Register and merge the town ——— state coarse ——— 6

<>If I understand the meaning of the question well, the intention of the question should be hail, and the accompaniment is to do this, and I hope it will help you.

Your expression is a bit problematic, it should be asking:

Solution 9 10 11) 8 (8 1 8 2 8 3) 8 3 (1 2 Zhichang 3) 8 Defeat 3 6 8.

8 9 10) 7 (9 10 11) 8 (10 11 12) 9 (11 12 13) 10 (1 7 1 8 1 9 1 10).

Note: Please pay attention to the correct use of parentheses to avoid misunderstandings.

The title is not very clear, so that there is a simple algorithm, Qing Chan is like a line difference map.

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You start by simplifying the square difference in algebra.

Multiply both sides by 1 2 to get.

64（1-1/2^n)=62

Divide by 64 on both sides.

1-1/2^n=62/64=31/32

Left and right swapping. 1-31/32=1/2^n=1/32

So 2 n = 32

2^5=32n=5

1/2^n

Is it the meaning of 2 to the nth power?

5a-3b=1……①

3a+20b-15c=24……②

15b+17c=-11……③

3 gets 15a-9b=3 5 gets -15a+100b-75c=120

The sum of the two formulas yields 91b-75c = 123 ......④

91 gives -1365b+1547c=-1001 15 gives 1365b-1125c=1845, and the sum of the two formulas gives 422c=844

c=2 is then substituted into the original formula, and b=3 is obtained

Then substitute into the original formula, and get a=2