横向
1
Number less than zero
3
U-shaped curve of a quadratic function
5
Math using letters for unknown values
8
Steepness of a line
12
Repeated addition
纵向
2
Single numeral from 0 to 9
3
Number greater than zero
4
Middle value in an ordered dataset
6
Longest side of a right triangle
7
Number with digits after a point
9
Rectangular array of numbers
10
System of ordered marks for measuring
11
Mathematical statement of equality
13
Number that divides evenly into another