# SOLUTION: I just took a math test and wanted to see if I had done this right. 10. Factor 512y^3-729 I determined that each side of this expression was a cube. 8^3=512, 9^3=729.

Algebra ->  Algebra  -> Polynomials-and-rational-expressions -> SOLUTION: I just took a math test and wanted to see if I had done this right. 10. Factor 512y^3-729 I determined that each side of this expression was a cube. 8^3=512, 9^3=729.      Log On

 Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations! Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

 Algebra: Polynomials, rational expressions and equations Solvers Lessons Answers archive Quiz In Depth

 Click here to see ALL problems on Polynomials-and-rational-expressions Question 350620: I just took a math test and wanted to see if I had done this right. 10. Factor 512y^3-729 I determined that each side of this expression was a cube. 8^3=512, 9^3=729. So I answered: (8y x 8y x 8y)-(9 x 9 x 9). Was this correct?Answer by nerdybill(7003)   (Show Source): You can put this solution on YOUR website!Hate to be a bearer of bad news but you didn't get it right. . 512y^3-729 can be rewritten (as you say) as: (8y)^3-9^3 At this point you have a "difference of cubes" -- a special case for factoring: a^3 – b^3 = (a – b)(a^2 + ab + b^2) . which then gives you: (8y - 9)((8y)^2 + (8y)(9) + 9^2) (8y - 9)(64y^2 + 72y + 81)