Across
1
Lines that never intersect
5
Parts per hundred
6
Part of a whole number
7
Exact correspondence on both sides
9
Number divisible only by 1 and itself
Down
2
Divisible by two
3
Steepness of a line
4
Total distance around a shape
8
Value that does not change
10
Single numeral from 0 to 9
11
Three-sided polygon
12
Line segment connecting two circle points