横向
1
Steepness of a line
4
Line segment connecting two circle points
5
Comparison of two quantities
7
Number less than zero
10
Math using letters for unknown values
12
Symbol representing unknown value
13
Result of addition
纵向
2
Parts per hundred
3
Lines that never intersect
6
Difference between highest and lowest values
8
Part of a line with two endpoints
9
Reference line in a graph
11
Rectangle with four equal sides