Across
1
Value that does not change
4
Amount of space an object occupies
5
Total distance around a shape
6
Three-sided polygon
12
Middle value in an ordered dataset
13
Proven mathematical statement
Down
2
Closed shape with straight sides
3
Part of a whole number
7
Rectangle with four equal sides
8
System of ordered marks for measuring
9
Single numeral from 0 to 9
10
Part of a circle's circumference
11
Rectangular array of numbers