Across
1
Value that does not change
5
Single numeral from 0 to 9
6
Math using letters for unknown values
7
U-shaped curve of a quadratic function
9
Round shape with all points equidistant
11
Result of addition
12
Rectangle with four equal sides
Down
2
The number representing nothing
3
Three-sided polygon
4
Reference line in a graph
5
Line crossing from corner to corner
8
Corner point of a polygon
10
Number with digits after a point