Question 236041
Comment:
The roots are: 
(-b/(2a) + [sqrt(b^2-4ac]/(2a)
(-b/(2a) - [sqrt(b^2-4ac]/(2a)
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If you add these you will get 2(-b/2a) = -b/a
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If you multiply them them you will get:
(-b/2a)^2 - {[sqrt(b^2-4ac]/(2a)}^2
= (b^2/4a^2) - [(b^2-4ac)/(4a^2)]
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= +4ac/(4a^2)
= c/a
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The sum of the roots of the equation x squared - 20x = 0 is_____________________.
The sum of the roots of a quadratic are 2(-b/(2a) = -b/a
Your Problem:
a = 1 ; b = -20 ; c = 0
Sum of roots = -(-20/1) = 20
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The product of its roots is_________________.
The product of the roots is c/a = 0/1 = 0


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Cheers,
Stan H.