横向
1
System of ordered marks for measuring
3
Rectangular array of numbers
4
Closed shape with straight sides
8
Total distance around a shape
9
Lines that never intersect
11
Line segment connecting two circle points
12
Number less than zero
13
Line touching circle at one point
14
Sum divided by count
纵向
2
Symbol representing unknown value
5
Proven mathematical statement
6
Exact correspondence on both sides
7
Longest side of a right triangle
10
Single numeral from 0 to 9
15
Part of a whole number