Across
1
Single numeral from 0 to 9
3
Distance from center to edge of circle
4
Three-sided polygon
7
Parts per hundred
8
Lines that never intersect
9
Rectangular array of numbers
10
U-shaped curve of a quadratic function
Down
2
Number greater than zero
3
Comparison of two quantities
5
Divisible by two
6
Sum divided by count
9
Repeated addition
11
Mathematical rule or equation