SOLUTION: X^3-5x^2-x=0 solve for x

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Question 996297: X^3-5x^2-x=0 solve for x
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E3-5x%5E2-x=0+
x%28x%5E2-5x-1%29=0+
one solution is highlight%28x=0%29
now use quadratic formula to find other two solutions
%28x%5E2-5x-1%29=0+
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-5%29+%2B-+sqrt%28+%28-5%29%5E2-4%2A1%2A%28-1%29+%29%29%2F%282%2A1%29+

x+=+%285+%2B-+sqrt%28+25%2B4+%29%29%2F2+

x+=+%285+%2B-+sqrt%28+29+%29%29%2F2+
exact solutions:
highlight%28x+=+%285+%2B+sqrt%28+29+%29%29%2F2%29+
highlight%28x+=+%285+-+sqrt%28+29+%29%29%2F2+%29
approximate solutions:
x+=+%285+%2B+sqrt%28+29+%29%29%2F2+=>x+=+%285+%2B+5.4%29%2F2+=>x+=+10.4%2F2+=>highlight%28x+=+5.2%29+
x+=+%285+-+sqrt%28+29+%29%29%2F2+=>x+=+%285+-+5.4%29%2F2+=>x+=+-0.4%2F2+=>highlight%28x+=+-0.2+%29