1, find the factor of a number, and find it one by one in an orderly manner, without repetition or omission. The smallest factor of a number is 1, and the largest factor is itself. The number of factors of a number is limited. The factor of 1 is only 1, which means 1.

2, a number (except 0) multiplied by a number greater than 1, the product is greater than the original number.

3. Multiplication and exchange law: when two numbers are multiplied, the position of the exchange factor remains unchanged.

4. Multiplication and association law: When three numbers are multiplied, the first two numbers are multiplied, or the last two numbers are multiplied first and then the third number, and their products are unchanged.

5. One-dimensional linear equation: An equation with an unknown number of one degree is called one-dimensional linear equation. Example method and calculation of learning linear equation of one variable. That is, an example is given to illustrate that the formula is replaced by χ and calculated.