Across
1
Part of a circle's circumference
3
Number that divides evenly into another
5
Line crossing from corner to corner
8
The number representing nothing
10
Mathematical statement of equality
11
Total distance around a shape
13
System of ordered marks for measuring
Down
2
Round shape with all points equidistant
4
Line segment connecting two circle points
6
Number divisible only by 1 and itself
7
Number greater than zero
9
Part of a line with two endpoints
12
Mathematical rule or equation