20 14 how to write the first question on page 25 of the first volume of the sixth grade mathematics book for primary schools?
Because they are all at 45 degrees, and the diagonal length of the small square is 10m, point (3,3) is 30m northeast of point (0,0), point (6,0) is 20m southwest of point (4,2), and point (6,7) is 65m northeast.