横向
1
Divisible by two
4
Line crossing from corner to corner
6
Lines that never intersect
8
Middle value in an ordered dataset
纵向
2
Number divisible only by 1 and itself
3
Math using letters for unknown values
4
Single numeral from 0 to 9
5
Rectangular array of numbers
7
Mathematical rule or equation
9
Longest side of a right triangle