Equation, referred to as equation for short, is an equation with unknown numbers. In equations, identities are called identities, and contradictions are called contradictory equations. For example, the solution of an unknown quantity in which x+ 1 = x can make the left and right sides of the equation equal is called the solution of the equation. The process of finding the solution of the equation or explaining that the equation has no solution is called solving the equation.

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Equation is a form of arithmetic, and the required answer is unknown, which is expressed in English letters. But remember! Don't use o, pay attention to the small letters l and z like numbers. The equation has no multiplication sign or division sign except the unknown. Unknown number multiplied by number can be tied, but unknown number is necessary; The division is indicated by dotted lines. When doing an application problem, there will be a sentence, that is, let ... be (English letters). The next step is to formulate the equation. But the unknown must be together with some numbers, such as (n+3=5) and (n = ...), which are strictly prohibited! Because this is a formula, and then the equation, the answer. There must be an answer to apply the equation! Don't write the unit after the answer. The algorithm of the equation is inverse calculation. For example, n+3=5, you have to subtract 3 from the left and right sides to find the balance. It's like Libra. Delete 3 directly on the left and subtract 3 directly on the right, which is the transfer item. When moving an item, the equal sign is symbol conversion, multiplication and division, addition and subtraction. When processing, add and subtract first, then multiply and divide, and finally bracket, that is, count down. Parentheses should be added and subtracted on the dividing line. So is multiplication. The timing of the number and the unknown plus the number [2(n+3)] can be calculated by the property of multiplicative distribution and become 2n+6. Finally, if you find two unknowns, there must be two equations; if you find three, there must be three … and so on. 2007-05-1310:1:03 Supplement: The advantage of the equation is that it can be used to calculate the numbers in the formula, such as the height of the trapezoid, because it will be troublesome to multiply and divide each value by the area, and it will be easy to calculate the height into the formula.

Equation is a mathematical problem, which is to calculate the value of an unknown from an unknown. If you want to know a certain number, you don't know how to use the math+or-. You can work out the unknown with equations. Example: My brother took 10 yuan out.

When I got home, only 2 yuan's money was left.

How much did my brother spend? [First set the question answer] [Let Y be unknown] Let Brother spend Y yuan.

[Enumeration equation] y+2= 10 y= 10-2 y=8 [Answer sentence] Brothers used 8 yuan. As long as the equation can be used well, "many unknowns can be solved"

Equation equation or equation for short is an equation with unknown numbers. In the equation, identities are called identities, for example, (y+2)? =y？ +4y+4； Contradictions are called contradictory equations. For example, the solution of an unknown number that x+ 1 = x can make the left and right sides of the equation equal is called the solution of the equation. The process of finding the solution of the equation or explaining that the equation has no solution is called solving the equation. The principle of solving the equation The same number or algebraic expression is added and subtracted from both sides of the equation at the same time, and the solution of the equation remains unchanged. When both sides of the equation are multiplied or divided by a number or algebraic expression that is not 0 at the same time, the solution of the equation remains unchanged. Classification of equations Algebraic equations Rational equations Integral equations Primary equations Quadratic equations Cubic equations Quadratic equations Higher order equations Fractional equations Unreasonable equations Transcendental equations

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Equation: Method of using mutual bottom pin

Such as multiplication and creep.

Increase or decrease. This equation is like a balance.

Unilateral reduction

The other must be reduced. Example: A+7 = 9 A+7-7 = 9-7 A = 2 2007-05-18: 57: 48 Supplement: Because of the format problem, the real question equation 3 = right, namely:? ===?

Equation, referred to as equation for short, is an equation with unknown numbers. In the equation, the identity is called the identity, and the solution of the unknown that can make the left and right sides of the equation equal is called the solution of the equation. The process of finding the solution of the equation or explaining that the equation has no solution is called solving the equation. For example, 2a = 38a =19a+9 =10x =1b-3 = 99b =102c/4 = 4c =16.

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For example: y+1=10y+1-1=1y = 9.

An equation refers to an equation with unknown numbers, which is called an equation. As for the one-dimensional linear equation and the two-dimensional linear equation, they are named according to the number of unknowns or unknowns contained in the equation. For example: x+5=7, x+y=8 (equation) x+5=7 (linear equation with one variable) x+y=8 (linear equation with two variables).

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Algebraic number formula ...................

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For example, m+12 = 20m+12-12 = 20-12m = 8.