Across
1
Space between two intersecting lines
4
Difference between highest and lowest values
5
Single numeral from 0 to 9
6
Part of a circle's circumference
9
Number that divides evenly into another
10
Comparison of two quantities
Down
2
Value that does not change
3
Mathematical rule or equation
7
Result of raising a number to an exponent
8
System of ordered marks for measuring
11
Number less than zero
12
Longest side of a right triangle
13
Divisible by two