Across
1
Number divisible only by 1 and itself
4
Lines that never intersect
5
Total distance around a shape
6
Line touching circle at one point
9
U-shaped curve of a quadratic function
10
Distance from center to edge of circle
Down
2
Part of a whole number
3
Number with digits after a point
7
Symbol representing unknown value
8
Mathematical rule or equation
11
Steepness of a line
12
Amount of space an object occupies
13
Sum divided by count