SOLUTION: What is the value of k if one exact x-intercept of y=x^2+kx+1 is 3+2sqrt2 ?

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Question 119293: What is the value of k if one exact x-intercept of y=x^2+kx+1 is 3+2sqrt2 ?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the value of k if one exact x-intercept of y=x^2+kx+1 is 3+2sqrt2 ?
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If 3+2sqrt2 is a root f(3+2sqrt2)=0
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Therefore: (3+2sqrt2)^2 + k(3+2sqrt2)+1 = 0
k(3+2sqrt2)= -(3+2sqrt2)^2-1
k = -(3+2sqrt2) -1/(3+2sqrt2)
k = -(3+2sqrt2) - (3-2sqrt2)/(9-8)
k = -3-2sqrt2-3+2sqrt2
k = -6
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Cheers,
Stan H.