Across
1
Symbol representing unknown value
3
Part of a line with two endpoints
6
Reference line in a graph
9
Number less than zero
10
Number greater than zero
11
Divisible by two
Down
2
Part of a circle's circumference
3
Collection of distinct elements
4
Number divisible only by 1 and itself
5
Result of addition
7
Difference between highest and lowest values
8
Corner point of a polygon