How do I rewrite 81x^10 y^5?

Question

It's example #9 from this site: http://www.wtamu.edu/academic/anns/mps/math/mathlab/col_algebra/col_alg_tut4_radical.htm

I don't understand why they used x^9 and y^3

Answer 1

I'm not entirely sure what your question is, but the ^ sign means "to the power of". So what you have there is 81x to the 10th power and y to the 5th power. If you want to know how to write them by hand, write 81x, then in the right hand corner above the x put a small 10. Hope that helped some.
Oh, and to the power of means multiplied by itself, so y^5 is y times y times y times y times y.