Across
1
Sum divided by count
3
System of ordered marks for measuring
4
Number divisible only by 1 and itself
5
Corner point of a polygon
7
The number representing nothing
8
Comparison of two quantities
12
Number less than zero
Down
2
Power to which a number is raised
3
Exact correspondence on both sides
6
Number that divides evenly into another
9
Mathematical rule or equation
10
Mathematical statement of equality
11
Split into equal parts
13
Closed shape with straight sides