math

2. the "middle value" in a series of numbers ordered from least to greatest.
3. the repeated addition of the same number
8. a form of math that usually deals with measuring and shapes
9. A three-sided polygon
11. the subject im doing this for
13. a simple operation that separates something into equal pieces
14. A statement that shows the equality of two expressions by joining them with an equals sign.
16. a polygon with four equal sides
18. putting 2 numbers together
20. a tool used for making mathematical calculations
21. A straight infinite path joining an infinite number of points in both directions

1. A number that divides into another number exactly
4. a branch of mathematics that substitutes letters for numbers.
5. The longest side of a right-angled triangle, always opposite to the right angle itself.
6. A quantity that is not whole that contains a numerator and denominator
7. A six-sided and six-angled polygon
10. The measure of how heavy something is.
11. the values that occur most frequently in a list of numbers
12. A number that divides another number into equal parts
15. The operation of finding the difference between two numbers
17. a letter used to represent a numerical value
19. the average of a group of numbers