Across
1
Repeated addition
4
Comparison of two quantities
5
Line crossing from corner to corner
7
Line touching circle at one point
8
Rectangular array of numbers
9
Longest side of a right triangle
10
Part of a circle's circumference
12
Lines that never intersect
Down
2
Symbol representing unknown value
3
Three-sided polygon
6
Line segment connecting two circle points
11
Power to which a number is raised