Across
1
Split into equal parts
2
Rectangle with four equal sides
4
Number less than zero
6
Part of a circle's circumference
9
Proven mathematical statement
10
Parts per hundred
Down
2
System of ordered marks for measuring
3
Divisible by two
5
Total distance around a shape
7
Steepness of a line
8
Number that divides evenly into another
11
U-shaped curve of a quadratic function