Across
1
Result of multiplication
4
Proven mathematical statement
5
Symbol representing unknown value
6
Number greater than zero
7
Sum divided by count
8
Total distance around a shape
Down
1
Lines that never intersect
2
System of ordered marks for measuring
3
The number representing nothing
9
Split into equal parts
10
Distance from center to edge of circle
11
Steepness of a line
12
Corner point of a polygon
13
Reference line in a graph