Across
1
Part of a circle's circumference
3
Longest side of a right triangle
4
Proven mathematical statement
5
Part of a line with two endpoints
7
U-shaped curve of a quadratic function
8
Number that divides evenly into another
Down
2
Three-sided polygon
6
Exact correspondence on both sides
7
Number divisible only by 1 and itself
9
Mathematical statement of equality