Across
1
Longest side of a right triangle
9
The number representing nothing
10
Result of addition
11
Round shape with all points equidistant
12
Result of multiplication
Down
2
Symbol representing unknown value
3
Comparison of two quantities
4
Parts per hundred
5
Difference between highest and lowest values
6
Distance from center to edge of circle
7
Repeated addition
8
Three-sided polygon