Across
1
Line touching circle at one point
6
Divisible by two
7
Part of a circle's circumference
8
Part of a whole number
9
Total distance around a shape
10
Space between two intersecting lines
12
System of ordered marks for measuring
13
Closed shape with straight sides
Down
2
Number that divides evenly into another
3
Symbol representing unknown value
4
Rectangular array of numbers
5
Value that does not change
11
Exact correspondence on both sides
12
Steepness of a line