Across
1
Symbol representing unknown value
6
Steepness of a line
7
Part of a circle's circumference
8
Part of a line with two endpoints
9
Round shape with all points equidistant
10
Number less than zero
12
Reference line in a graph
Down
2
Divisible by two
3
The number representing nothing
4
Mathematical statement of equality
5
Rectangle with four equal sides
11
Line crossing from corner to corner