Across
1
Split into equal parts
5
The number representing nothing
6
Proven mathematical statement
10
Collection of distinct elements
11
U-shaped curve of a quadratic function
12
System of ordered marks for measuring
Down
2
Three-sided polygon
3
Corner point of a polygon
4
Reference line in a graph
7
Distance from center to edge of circle
8
Lines that never intersect
9
Symbol representing unknown value