SOLUTION: If the product of the roots x2-3x+k=10 alpha*Bita=-2 find out k

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Question 947871: If the product of the roots x2-3x+k=10
alpha*Bita=-2 find out k
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-3x%2Bk-10=0

General solution of quadratic equation to find and use the roots to form the described description:

%28%283%2Bsqrt%289-4%28k-10%29%29%29%2F2%29%28%283-sqrt%289-4%28k-10%29%29%29%2F2%29=-2
%281%2F4%29%283%2Bsqrt%289-4%28k-10%29%29%29%283-sqrt%289-4%28k-10%29%29%29=-2
Recognize the makings of Difference Of Squares
%281%2F4%29%289-%289-4%28k-10%29%29%29=-2
%281%2F4%29%280%2B4%28k-10%29%29=-2
k-10=-2
k=-2%2B10
highlight%28k=8%29