Across
1
Total distance around a shape
6
System of ordered marks for measuring
8
Middle value in an ordered dataset
10
Math using letters for unknown values
12
Distance from center to edge of circle
13
Closed shape with straight sides
Down
2
Rectangle with four equal sides
3
The number representing nothing
4
Mathematical rule or equation
5
Part of a whole number
7
Exact correspondence on both sides
9
Power to which a number is raised
11
Line segment connecting two circle points