You can put this solution on YOUR website! This problem is a difference of cubes so the final answer has to end with the formula in this format: (x+y)(x^2-xy+y^2).
Your problem 125r^3-8s^3 the cube root of 125r^3 is 5r and the cube root of 8s^3 is 2s. Knowing that you now use the format above to plug in those numbers in for x and y giving you....
(5r+2s)(5r^2-((5r)(2s))+2s^2)
now you multiply the middle together giving you your final answer of....
(5r+2s)(5r^2-10rs+2s^2)