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PLEASE HELP!!!!!!!!!

Let x^2+bx+c = 0 be a quadratic whose roots are each two more than the roots of 3x^2-5x-7. What is c?

User TEN Design
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1 Answer

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Let
x_1 , x_2 be the roots of the equation
3x^2-5x-7. By the Viet theorem you have that
\left \{ {{x_1+x_2=- (5)/(3) } \atop {x_1x_2= (-7)/(3) }} \right..

For the equation
x^2+bx+c = 0 you'll have that
c=(x_1+2)(x_2+2)=x_1x_2+2(x_1+x_2)+4=(-7)/(3)+2\cdot(- (5)/(3) )+4
That is
(-7)/(3)- (10)/(3) +4=- (5)/(3).

Answer:
- (5)/(3)
User Andre Mesquita
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