Across
1
Total distance around a shape
6
Proven mathematical statement
7
Reference line in a graph
9
Three-sided polygon
Down
1
Closed shape with straight sides
2
Mathematical statement of equality
3
Comparison of two quantities
4
System of ordered marks for measuring
5
Rectangular array of numbers
8
Line crossing from corner to corner
10
Number divisible only by 1 and itself
11
Line touching circle at one point