SOLUTION: find the value of c in the equation 12x^2 + 20x + c = 0 so that the sum and product of the roots are equal

Question 1187624: find the value of c in the equation 12x^2 + 20x + c = 0 so that the sum and product of the roots are equal
Answer by ikleyn(52793) (Show Source): You can put this solution on YOUR website!
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find the value of c in the equation 12x^2 + 20x + c = 0 so that the sum and product of the roots are equal.
~~~~~~~~~~~~~~~~~~

Nothing is easier.

According to Vieta's theorem, the sum of the roots is equal to    
and the product of the roots is  .


Since the sum of the roots equals to the product of the roots, we have this equality


     = .


It gives  c = -20.      ANSWER

Solved.

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