横向
1
Closed shape with straight sides
6
Sum divided by count
7
Collection of distinct elements
8
Value that does not change
9
Middle value in an ordered dataset
11
Math using letters for unknown values
纵向
2
Part of a line with two endpoints
3
Symbol representing unknown value
4
Mathematical statement of equality
5
Power to which a number is raised
10
Repeated addition
12
Total distance around a shape
13
Part of a whole number