SOLUTION: need to solve by completing the square. 9x^2+27x-4=0

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Question 769821: need to solve by completing the square. 9x^2+27x-4=0
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
9x%5E2%2B27x-4=0
/9
x%5E2%2B3x-%284%2F9%29=0

Third term = (1/2 the co-efficient of second term)^2
=(1/2 *3)^2
=9/4
x%5E2%2B3x%2B%289%2F4%29+-9%2F4-4%2F9=0
%28x%2B%283%2F2%29%29%5E2+=+9%2F4+%2B+4%2F9
%28x%2B%283%2F2%29%29%5E2=%2897%2F36%29
take square root
x+(3/2) = +/-sqrt(97)/6
x= -(3/2)+sqrt(97)/6 OR -(3/2)-sqrt(97)/6