Across
1
Number divisible only by 1 and itself
2
Result of addition
4
Line touching circle at one point
5
Part of a circle's circumference
6
Three-sided polygon
7
Comparison of two quantities
8
Symbol representing unknown value
Down
1
Parts per hundred
2
Rectangle with four equal sides
3
Number with digits after a point
9
Rectangular array of numbers
10
Line segment connecting two circle points
11
The number representing nothing