横向
1
The number representing nothing
3
Math using letters for unknown values
5
Result of addition
6
Middle value in an ordered dataset
9
Mathematical statement of equality
10
Total distance around a shape
11
U-shaped curve of a quadratic function
纵向
2
Symbol representing unknown value
4
Number greater than zero
7
Difference between highest and lowest values
8
Lines that never intersect
12
Mathematical rule or equation