Across
1
Sum divided by count
4
The number representing nothing
5
Lines that never intersect
6
Corner point of a polygon
10
Result of raising a number to an exponent
11
Number less than zero
12
Proven mathematical statement
13
Reference line in a graph
Down
1
Part of a circle's circumference
2
Distance from center to edge of circle
3
Power to which a number is raised
7
Total distance around a shape
8
Split into equal parts
9
Collection of distinct elements