Across
1
Line segment connecting two circle points
4
Single numeral from 0 to 9
5
Line crossing from corner to corner
6
Reference line in a graph
7
Amount of space an object occupies
9
Comparison of two quantities
11
Corner point of a polygon
Down
2
Longest side of a right triangle
3
Sum divided by count
8
Number divisible only by 1 and itself
10
Number with digits after a point
12
Proven mathematical statement