Across
1
Mathematical statement of equality
5
Difference between highest and lowest values
6
Number divisible only by 1 and itself
7
Steepness of a line
8
Rectangle with four equal sides
10
Number less than zero
12
Repeated addition
Down
2
Round shape with all points equidistant
3
Result of raising a number to an exponent
4
Symbol representing unknown value
8
Result of addition
9
Split into equal parts
11
Lines that never intersect
13
Number greater than zero