横向
1
U-shaped curve of a quadratic function
5
Amount of space an object occupies
6
Steepness of a line
9
Line segment connecting two circle points
10
Distance from center to edge of circle
12
The number representing nothing
13
Reference line in a graph
纵向
2
Repeated addition
3
Number divisible only by 1 and itself
4
Result of multiplication
7
Number with digits after a point
8
Number less than zero
11
Sum divided by count