Across
1
Sum divided by count
5
Repeated addition
6
Reference line in a graph
8
Difference between highest and lowest values
10
Value that does not change
11
Longest side of a right triangle
12
Line touching circle at one point
Down
2
Mathematical statement of equality
3
Rectangle with four equal sides
4
Space between two intersecting lines
7
System of ordered marks for measuring
9
Amount of space an object occupies
13
Part of a circle's circumference