SOLUTION: If the two roots of the quadratic 7x^2+3x+k$ are (-3張sqrt(299))/14, what is k?

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Question 1086048: If the two roots of the quadratic 7x^2+3x+k$ are (-3張sqrt(299))/14, what is k?
Found 2 solutions by ikleyn, MathTherapy:
Answer by ikleyn(52788)   (Show Source): You can put this solution on YOUR website!
.
 is the product of the roots (Vieta's theorem):

 =  =  = .


Hence, k =  = 11.


Thanks to @MathTherapy for pointing my typo in my previous version.


Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!

If the two roots of the quadratic 7x^2+3x+k$ are (-3張sqrt(299))/14, what is k?
Product of the roots = 
Roots: =====> and
We then get:
Reducing, we get:
------ Cross-multiplying

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