Across
1
Rectangular array of numbers
4
The number representing nothing
5
Closed shape with straight sides
6
Split into equal parts
8
Result of addition
9
Part of a circle's circumference
10
Steepness of a line
12
Round shape with all points equidistant
Down
2
Line crossing from corner to corner
3
Repeated addition
7
Visual representation of data
11
System of ordered marks for measuring