Across
1
Power to which a number is raised
4
Rectangle with four equal sides
5
Repeated addition
6
The number representing nothing
9
Number greater than zero
11
Closed shape with straight sides
Down
2
Steepness of a line
3
Comparison of two quantities
4
Exact correspondence on both sides
5
Middle value in an ordered dataset
7
Single numeral from 0 to 9
8
Reference line in a graph
10
Lines that never intersect