SOLUTION: -4x^2-9x-6=0 please help me solve this quadratic equation

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Question 664215: -4x^2-9x-6=0 please help me solve this quadratic equation
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
-4x%5E2-9x-6=0
Divide by -1
4x%5E2%2B9x%2B6=0
factorize by completing the squares method
4x%5E2%2B9x=-6
add (81/4) on both sides
4x%5E2%2B9x%2B%2881%2F4%29+=+-6-%2881%2F4%29

%282x%2B%289%2F2%29%29%5E2=-105%2F4
take the square root
2x+(9/2) = +/- sqrt(-105/4)

2x= -(9/2) +/- sqrt(105)*i/2
x= (-9/4) +/- sqrt(105)*i/4