Question

can someone help me simplify this: the quantity 10 times x to the 6th power times y to the third power plus 20 times x to the third power times y to the 2nd power all over 5 times x to the third power times y

Answer 1

10x^6y^3 + 20x^3y^2 / 5x^3y = 
5x^3y (2x^3y^2 + 4y) / 5x^3y=
2x^3y^2 + 4y

First you find what the expressions 10x^6y^3 and 20x^3y^2 have in common, and that is 5x^3y, which is the same as the denominator, so you can easily divide them and get 1. 
Hope you understand!