Across
1
Three-sided polygon
3
Line segment connecting two circle points
6
Rectangular array of numbers
8
Steepness of a line
9
Result of multiplication
11
Number with digits after a point
Down
2
Power to which a number is raised
4
Single numeral from 0 to 9
5
Proven mathematical statement
7
Difference between highest and lowest values
10
Longest side of a right triangle
12
Sum divided by count