Across
1
Single numeral from 0 to 9
4
Amount of space an object occupies
5
Mathematical statement of equality
6
Divisible by two
7
Proven mathematical statement
8
System of ordered marks for measuring
13
Space between two intersecting lines
Down
2
Longest side of a right triangle
3
Number divisible only by 1 and itself
9
Line crossing from corner to corner
10
Part of a whole number
11
Exact correspondence on both sides
12
Symbol representing unknown value