Across
1
Distance from center to edge of circle
4
The number representing nothing
5
Middle value in an ordered dataset
6
Round shape with all points equidistant
7
Total distance around a shape
8
Symbol representing unknown value
Down
2
Sum divided by count
3
Number less than zero
6
Line segment connecting two circle points
9
Three-sided polygon
10
Lines that never intersect
11
Number divisible only by 1 and itself
12
Part of a line with two endpoints
13
Rectangular array of numbers
14
Difference between highest and lowest values