algebra

2. a combination of numbers, variables, functions
4. Terms whose variables with exponents are the same
6. where the function has a negative slope.
9. based on or in accordance with reason or logic
10. as great, high, or intense as possible or permitted.
13. the way in which factors are grouped in a multiplication problem does not change the product.
15. the principal or horizontal axis of a system of coordinates, points along which have a value of zero for all other coordinates.
17. the point or place where something begins, arises, or is derived.
18. A grouping of terms or values that use a sign to show an equal relationship — that two quantities are equal
20. a whole number; a number that is not a fraction.

1. the highest point; the top or apex.
3. To find the answer. In algebra, it means to figure out what the variable stands for.
5. To combine all that can be combined, reduce the number of terms, and put an expression in an easily understandable form.
7. with addition and multiplication of numbers, you can change the order of the numbers in the problem and it will not affect the answer.
8. the axis of a plane Cartesian coordinate system parallel to which ordinates are measured
11. a number or algebraic expression that divides another number or expression evenly—i.e., with no remainder.
12. A small number written slightly above and to the right of a variable or number. It’s used to show repeated multiplication.
14. the least or smallest amount or quantity possible, attainable, or required.
16. A value or number that never changes in an equation — it's constantly the same
19. A grouping together of one or more factors (variables and/or numbers), such as 4.