SOLUTION: please help me solve this equation {{{x^3 + 5x = 79.4}}}

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Question 169175: please help me solve this equation x%5E3+%2B+5x+=+79.4
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
x^3+5x=79.4
x^2+5x-79.4=0
Using the quadratic equationx+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+we get:
x=(-5+-sqrt[5^2-4*1*-79.4])/2*1
x=(-5+-sqrt[25+317.6 ])/2
x=(-5+-sqrt342.6)/2
x=(-5+-18.51)/2
x=-5+18.51)/2
x=13.51/2
x=6.755 ans.
x=(-5-18.51)/2
x=-23.51/2
x=-11.755 ans.