SOLUTION: What is the sum of the squares of the roots of 18x^2 +21x - 400?

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Question 1084246: What is the sum of the squares of the roots of 18x^2 +21x - 400?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
18x^2 +21x - 400
x=(1/36)(-21+/- sqrt (441+28800); sqrt (29241)=171
roots are 150/36 and -192/36 or 4.167 and -5.33
(25/6)^2+(16/3)^2=45.81
625/36+256/9
=625/6+1024/36
=1649/36 (exact)
graph%28300%2C300%2C-20%2C20%2C-100%2C100%2C18x%5E2%2B21x-400%29