SOLUTION: Which is a list of all the roots of x^5 + 7x^4=18x^3

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Question 953266: Which is a list of all the roots of x^5 + 7x^4=18x^3
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E5+%2B+7x%5E4=18x%5E3
x%5E5+%2B+7x%5E4-18x%5E3=0
%28x%5E2+%2B+7x-18%29x%5E3=0
%28x%5E2+-2x%2B+9x-18%29x%5E3=0
%28%28x%5E2+-2x%29%2B+%289x-18%29%29x%5E3=0
%28x%28x+-2%29%2B9+%28x-2%29%29x%5E3=0
%28%28x%2B9%29%28x-2%29%29x%5E3=0
solutions:
if %28x%2B9%29+=0=>x=-9
if+%28x-2%29=0=>x=2
if x%5E3=0=>x=0 (triple solution)
a list of all the roots:x=0,x=2,x=-9