Across
1
Rectangular array of numbers
4
Symbol representing unknown value
6
Lines that never intersect
7
Line crossing from corner to corner
9
Collection of distinct elements
11
Proven mathematical statement
12
System of ordered marks for measuring
Down
2
Split into equal parts
3
Exact correspondence on both sides
5
Parts per hundred
8
Number with digits after a point
10
Amount of space an object occupies
13
U-shaped curve of a quadratic function