SOLUTION: If one root of a quadratic equation is 3 and the product of the roots is 15, what is the value of b if the equation is in the form {{{ ax^2+bx+c = 0 }}} and a=1?
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Question 861377: If one root of a quadratic equation is 3 and the product of the roots is 15, what is the value of b if the equation is in the form and a=1? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! If one root of a quadratic equation is 3 and the product of the roots is 15, what is the value of b if the equation is in the form ax^2 + bx + c = 0 and a=1?
:
15/3 = 5 is the other root
FOIL
(x-3)*(x-5) = x^2 - 8x + 15
b = -8
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