Across
1
Math using letters for unknown values
4
Single numeral from 0 to 9
6
Three-sided polygon
8
Number greater than zero
11
Repeated addition
Down
2
Round shape with all points equidistant
3
Middle value in an ordered dataset
5
Part of a circle's circumference
6
Proven mathematical statement
7
Number less than zero
8
Number divisible only by 1 and itself
9
Result of addition
10
Parts per hundred