Across
1
Total distance around a shape
4
Reference line in a graph
6
Rectangle with four equal sides
7
Single numeral from 0 to 9
8
Lines that never intersect
9
Result of multiplication
12
System of ordered marks for measuring
Down
2
Rectangular array of numbers
3
Sum divided by count
4
Part of a circle's circumference
5
Power to which a number is raised
6
Result of addition
10
Symbol representing unknown value
11
Line touching circle at one point