Across
1
Single numeral from 0 to 9
3
Mathematical rule or equation
4
System of ordered marks for measuring
8
Round shape with all points equidistant
9
Number greater than zero
Down
2
Reference line in a graph
4
Result of addition
5
Collection of distinct elements
6
Steepness of a line
7
Split into equal parts
10
Part of a circle's circumference