The general equation is simple,
I'll help you calculate the specific figures.
Addition, subtraction, multiplication and division should be the opposite.
Special equations, don't be confused,
Subtract and divide by the unknown,
Add and multiply to get the average.
If it's a little complicated,
If you are far away, it is easy to know.
The specific analysis is as follows:
We can divide the equations in textbooks into three categories: general equations, special equations and slightly complicated equations.
Equations in the form of: x+a=b, x-a=b, ax=b, and x÷a=b can be called general equations.
Two kinds of equations, a- x =b and a÷x =b, can be called special equations.
AX+B = C and A (X-B) = C can be called slightly complicated equations.
We know that for a general equation, if a is added to the equation, a will be subtracted from both sides of the equation when solving by using the properties of the equation. Similarly, if a is used to subtract the equation, one will be added to both sides of the equation when solving it by using the properties of the equation. Multiplication and division are the same. In other words, addition, subtraction, multiplication and division are opposites, and addition, subtraction, multiplication and division are concrete numbers. To sum up, the general equation is very simple, and the specific numbers will be given to you. Addition, subtraction, multiplication and division should be the opposite.
For a special equation, both subtraction and division are unknowns X. When solving, subtract the unknowns and add the unknowns, divide the unknowns and multiply the unknowns, and the signs are opposite, so the equation is transformed into a general equation, which can be summarized as: don't be confused by the special equation, subtract the unknowns and divide them by the unknowns, and multiply them to become general.
For a slightly more complicated equation, the way I teach my children is to "keep the distance from the unknown X", that is, first remove those far from the unknown X and regard those far from the unknown X as a whole. Through transformation, the equation becomes simple and clear at a glance. To sum up: if it's a little complicated, it's easy to get out.
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