2. Using two numbers to indicate a position in turn is a number pair, and two data are needed to determine the position of an object.
3. When the position is represented by a number pair, which column is represented first, and then which row is represented. Don't confuse columns with rows.
4. When writing a number pair, enclose the number of columns and rows in brackets and separate them by writing a comma between them. Write: (column, row).
5. Logarithm of reading: (2,3) You can read (2,3) directly, or you can read it as a number pair (2,3).
6. A set of number pairs can only represent one position.
7. Number pairs representing the positions of objects in the same column have the same first number; A pair of numbers representing the position of an object in the same row, whose second number is the same.
Extended introduction:
1, number pair: consists of two numbers, separated by commas and enclosed by brackets. The numbers in brackets are the number of columns and the number of rows from left to right, that is, "columns first, then rows".
2. Function: A set of numbers sets the position of a unique point, and this principle is latitude and longitude. Example: In the grid diagram (plane rectangular coordinate system), it is represented by several pairs (3, 5) (third column, fifth row).
3. In the plane rectangular coordinate system, the coordinates on the X axis represent columns and the coordinates on the Y axis represent rows. For example, the number pair (3, 2) represents the third column and the second row.
4. The row number of the number pair (x, 5) remains unchanged, indicating a horizontal line, and the column number of (5, y) remains unchanged, indicating a vertical line (one number is uncertain and one point cannot be determined).