Across
1
Three-sided polygon
5
Repeated addition
6
Reference line in a graph
7
Value that does not change
10
Result of multiplication
12
Symbol representing unknown value
13
Power to which a number is raised
15
The number representing nothing
Down
2
Collection of distinct elements
3
Mathematical rule or equation
4
Proven mathematical statement
8
Distance from center to edge of circle
9
Divisible by two
11
Number that divides evenly into another
14
Line crossing from corner to corner