Across
1
Part of a line with two endpoints
5
Symbol representing unknown value
6
Longest side of a right triangle
7
Result of multiplication
8
Middle value in an ordered dataset
10
Total distance around a shape
12
U-shaped curve of a quadratic function
Down
1
Exact correspondence on both sides
2
Three-sided polygon
3
Math using letters for unknown values
4
Line touching circle at one point
9
Split into equal parts
11
Number divisible only by 1 and itself
13
Result of addition