Across
1
Line touching circle at one point
3
Part of a circle's circumference
5
Rectangle with four equal sides
8
Lines that never intersect
9
Number less than zero
11
Steepness of a line
Down
2
Mathematical rule or equation
4
Corner point of a polygon
5
Collection of distinct elements
6
U-shaped curve of a quadratic function
7
Mathematical statement of equality
10
Comparison of two quantities
12
Symbol representing unknown value