Across
1
Proven mathematical statement
5
Number less than zero
6
Exact correspondence on both sides
8
Line crossing from corner to corner
13
Single numeral from 0 to 9
Down
2
Divisible by two
3
Middle value in an ordered dataset
4
Rectangular array of numbers
7
Longest side of a right triangle
9
System of ordered marks for measuring
10
Part of a whole number
11
Repeated addition
12
Number divisible only by 1 and itself