I m a junior high school student, and tomorrow I ll take the one dimensional equation, and I just ca

The column equation is mainly to find the equivalence relationship, to put it bluntly, it is the equality relationship, which is generally a series of changes, what is equal to what. Finding this relationship, he translated Chinese into the language of mathematics as he said. Of course, there are some fixed question types, but don't worry, this thing needs to be practiced to have a feeling, seeing that you are so attentive, I guess there is no problem! Come on.

Understanding the question is key! Read it a few times, highlight the key points while reading, write out the known amount, think about the relationship between the unknown and the known, it's best to try it tonight, and I wish you a good score.

Be sure to grasp the meaning of the question, understand what the question asks, know the known and unknown, and then you can list the equations related to the topic according to the conditions, the main thing is to use it flexibly, come on, fight!!

You're a strong thinker, but equations can simplify the problem... Just treat what you are looking for as a column of x, one of which is known, and you take it as what you are asking for, and use your solution to the equation that doesn't lie, for example, 2=3x-1 or something, so you can do it!

1. Review the question carefully first and find out the equivalent relation.

2. Write a sentence again, and think about whether it is direct or indirect.

3. Equations according to the equiquantitative relation.

4. Solution.

Set the desired results as x, y, etc., and then list the equations according to the problem... Columns and systems of equations are a forward way of thinking...

You look at the question clearly, see what you are asking for, and then set it to x, and then look for the relationship with x according to the other conditions in the question, and that's it.

Ask the teacher and communicate with the teacher. After the teacher explains it to you, it's time to review.

I'm also a junior high school student, and I've taken this one, it's not difficult, and the equation must be able to find an equivalent relationship, otherwise it won't come out.

The key is to find an equivalence relationship.

The best way to learn math is to listen to the lectures when the teacher lectures! I will have trouble making up for school in the future.

Can't list a one-dimensional equation?

1.Denominator: Multiply by the least common multiple of each denominator on both sides of the equation;

2.Remove braces: first go to the small braces, then the middle brackets, and finally the braces; (Remember to change the sign if there is a minus sign outside the parentheses).

3.Shift: Move all terms with unknowns to one side of the equation and all other terms to the other side of the equation; The move item needs to be renumbered.

4.Merge similar terms: Equations are formed in the form ax=b(a≠0);

5.Coefficients are reduced to 1: Divide the coefficient a by the unknown number on both sides of the equation to get the solution of the equation x=b a

Remove the denominator and then brackets, move items and merge similar items.

The coefficient of 1 is not good, and it is not in vain to be accurate.

Unary Linear Equation Judgment Method:

By simplification, the equation that contains only one unknown and the highest order term that contains the unknowns is one is called a one-dimensional equation.

To determine whether an equation is a univariate equation, first look at whether it is an integral equation. If so, sort it out. If it can be organized in the form ax+b=0(a≠0), then the equation is a univariate equation.

There should be an equal sign in it, and there should be no unknown number in the denominator.

You can read more books and do more questions. You can also call the teacher and ask him to tell you again slowly.

It's okay, this kind of unimportant, the final exam doesn't account for a lot of points,

The main thing is to read the books first, the textbooks should explain it very clearly, if it really doesn't work, just ask the teacher

1.Wheat x kg x - 28% x = 1802Set the air ticket** to be x yuan x+(25-20) 3If the number of junior high school students in Guangzhou is x0,000, the number of primary school students is (2x+14) million.

x+（2x+14）=128

1, solution: 1) set up a total of schools to purchase hail laughing x potted flowers, according to the number of flowers assigned to each class is equal, there are.

5+(x-5) 10=10+[5+(x-5) 10-10] 10 solution: x=45

A: The school purchased a total of 45 potted flowers.

2) Take 5 + (45-5) 10 = 9 pots in one shift.

A: Each class is assigned 9 pots of flowers.

3) Because all classes take the same flowers, there are class digits.

45 9 = 5 classes.

A: There are 5 classes in this school.

2. Solution: The speed of the armor is xkm h

The sum of the velocities of A and B with people is: 18 9 5 = 10 km h, then: B's velocity is: (10 x) km h

Inspired by: 2 3 3 2) x 3 2 (10 x) 18x 15 3 2x 18

x Friends 3x

10－x＝10－

Answer: A's velocity is, B's velocity is.

3. Set the specified time to x

15*(x-15 60)=9*(x+15 60)x=1, that is, the distance is: 15*[1-15 60]=kilometers.

A: The distance from home to school is kilometers.

4. If the speed of the slowest athlete is x kilometers, then the speed of the fastest athlete is kilometers per hour.

List equations: (

Solve equations. Get: x=30

The fastest athlete travels at 42 kilometres in 35 minutes.

The slowest athlete travels 30 kilometers in 35 minutes and travels in kilometers.

5, (1) 550t+250t=400, t=minutes. A: A and B set off in opposite directions at the same time and in the same place, and they met again 1 2 minutes later.

2) 550t=250t+400, t=4 3 minutes. A: A and B set off in the same place and direction at the same time, and they met 4 3 minutes later.

3) If B is 100 places ahead of A at the time of starting, and A and B start at the same time and in the same place, ask how many minutes they will be after.

Second encounter.

The question is wrong, since B is 100 places in front of A, it is impossible for A and B to set off at the same time and place at the same time

550-250)t=100+400

t=5 3 A5 3 minutes later they met for the second time.

Hope it works for you, thanks.

The school has enough to get x pots of flowers.

5+(x-5)*1 10=15+-15}*1 10 gives x=855

5+(855-5)*1 stupid with 10=90

.No problem with the question?

855 90 is not an integer.

Keep dividing until you finish with a smile, and each class gets the same number of flower pots with rolling laughter?

Set the pedestrian speed to v

Suppose there is a tram leaving the starting point every x minutes at a speed of V'

During the same direction movement, the distance traveled by a pedestrian in 6 minutes = the distance traveled by tram (6-x) minutes is: 6v = (6-x)v'；

During the opposite movement, the distance traveled by a pedestrian in 2 minutes = the distance traveled by a tram (x-2) minutes: 2v = (2-x)v'；

v/v'=(6-x)/6=(2-x)/2

The unary equation is actually not difficult. According to the meaning of the question, you can understand the events described in the question and the relationship between the various quantities in order to correctly list the equations. The unary equation can directly reflect the quantitative relationship, and does not need to go through a complex analysis to find the result directly like in elementary school.

For example, if there are 20 pear trees and 5 more pear trees than apple trees, how many apple trees are there?

Suppose there are x apple trees, and the equation can be listed.

20-x=5 (this equation directly means that there are 5 more pear trees than apple trees) is solved, x=15

Of course, the above example is fairly simple and will feel completely unnecessary to you, but you need to grasp the idea of column equations and apply them later when solving complex problems.

You're going to write about the equivalence and you're going to write it slowly.

-。- Make a list of equations based on the question! Then solve the equation!!

I don't know.

I also wanted to ask.

If you don't understand, ask the teacher!!

You can't list equations or you can't solve equations.

Here's how I can solve a one-dimensional equation.

Idea analysis] is mainly to use the deformation of the equation [problem solving process] The equation has two elements, both of which are indispensable: (1) The equation must be an equation; (2) The equation must contain unknowns. Therefore, it can be said that equations are special equations, and their particularity lies in the fact that they contain unknowns.

It is also because of the unknowns that the equation is an undetermined equation; When an unknown number is taken to determine a value, the values on the left and right sides of the equation may or may not be equal. For example, when x=2, the left and right values of equation 5x-7=8 are not equal; When x=3, the left and right sides of equation 5x-7=8 are equal. If the values on the left and right sides of the equation are equal when an unknown is taken to determine a certain value, the value of the unknown is called the solution of the equation.

For example, 3 is the solution of the equation 5x-y=8, which is generally expressed by x=3, and the following two points should be paid attention to about the solution of the equation: (1) The value of the unknowns that make the left and right sides of the equation equal can be more than one, and the solution of the equation refers to the value of all these unknowns. (2) Conversely, if the solution of the equation is known to be a certain value of an unknown number, then the value of this unknown is substituted into the left and right sides of the equation, and the values on the left and right sides of the equation are equal, that is, the equation is a definite equation.

Equations can contain one or more unknowns. For an equation that contains only one unknown, its solution is also called a root. The concept of root is a new one.

This concept will be used later, for example, in the chapter "Unary Quadratic Equations" there is a formula for finding the root, the relationship between the root and the coefficient. The concept of roots is only for unary equations, and multivariate equations do not mention roots. There are many ways to solve equations, for example, the solution of equations 5x-7 8 can be found in the same way as in elementary school, or you can use the method learned in Chapter 1.

Regardless of the method, the process of finding the solution of an equation is called solving an equation. Solving an equation requires all the solutions of the equation. Solving an equation is actually purposefully and progressively deforming the original equation to obtain the form x=a.

These deformations should ensure that the equations obtained after deformation are the same as the original equation solutions, so that the final solution is the solution of the original equation. The deformations mentioned by the properties of the equation are guaranteed except that both sides of the equation are multiplied by 0, and these deformations are suitable for solving more complex equations, so that the solution of the unary equation can take advantage of the properties of the equation.