Across
1
Single numeral from 0 to 9
2
Symbol representing unknown value
4
Proven mathematical statement
5
Result of multiplication
9
Reference line in a graph
Down
2
Corner point of a polygon
3
Rectangular array of numbers
5
Lines that never intersect
6
Number divisible only by 1 and itself
7
Value that does not change
8
Number less than zero
10
Longest side of a right triangle