Across
1
Space between two intersecting lines
3
Line crossing from corner to corner
5
Distance from center to edge of circle
6
Symbol representing unknown value
9
Result of raising a number to an exponent
10
Round shape with all points equidistant
11
Number divisible only by 1 and itself
13
Part of a line with two endpoints
Down
2
Rectangular array of numbers
3
Split into equal parts
4
Difference between highest and lowest values
7
Mathematical statement of equality
8
The number representing nothing
12
Exact correspondence on both sides