Math crossword puzzle

1. least common multiple (the short cut)
8. the list of independent variables.
9. the mathematics of working with variable's.
11. first, outers, Inners, lasts.
14. the plane formed by a horizontal axis and a vertical axis.
15. number that occurs most often.
17. a number that has to be multiplied by itself three times.
18. the middle number(s) of the number list when in order from least to greatest.

2. a pair of numbers given a location on a grid.
3. the sum of difference of terms which have variable's raised to positive integer powers.
4. a mathematical sentence built from expressions using one or more equal signs.
5. another word for average.
6. Y variables in a function
7. polynomial with one term.
9. plural for axis
10. we're a negative turns to a positive with 2 bars.
12. coefficient: the coefficient of a polynomial's leading term.
13. polynomial with three terms.
16. polynomial with two terms.