Across
1
Mathematical rule or equation
3
Number divisible only by 1 and itself
4
Part of a circle's circumference
5
Corner point of a polygon
6
Math using letters for unknown values
7
Line touching circle at one point
10
Lines that never intersect
13
Result of multiplication
Down
2
Total distance around a shape
3
U-shaped curve of a quadratic function
4
Space between two intersecting lines
8
Number less than zero
9
Rectangle with four equal sides
11
Proven mathematical statement
12
Three-sided polygon