SOLUTION: A student factored 5y^3 + 55y^2 +90y by first factoring out 5y to get 5y(y^2 + 11y + 18). He wrote the answer (y + 2)(y + 9) as the factored answer. Why is this answer wrong?

Algebra ->  Equations -> SOLUTION: A student factored 5y^3 + 55y^2 +90y by first factoring out 5y to get 5y(y^2 + 11y + 18). He wrote the answer (y + 2)(y + 9) as the factored answer. Why is this answer wrong?      Log On


   



Question 315999: A student factored 5y^3 + 55y^2 +90y by first factoring out 5y to get
5y(y^2 + 11y + 18). He wrote the answer (y + 2)(y + 9) as the factored answer. Why is this answer wrong?

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A student factored 5y^3 + 55y^2 +90y by first factoring out 5y to get
5y(y^2 + 11y + 18). He wrote the answer (y + 2)(y + 9) as the factored answer. Why is this answer wrong?
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If you multiply (y + 2)(y + 9), you don't get 5y^3 + 55y^2 +90y, so it's wrong.