SOLUTION: Getting lost in completing the square for 2x^2+5x+11=0 I am able to get to 2x^2+5x=-11 then do I divide everything by 2? That would give me a really complicated fraction of x^2+5x

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Question 385173: Getting lost in completing the square for 2x^2+5x+11=0
I am able to get to 2x^2+5x=-11 then do I divide everything by 2? That would give me a really complicated fraction of x^2+5x/2=-11/2 then I am lost...
Melody
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
completing the square for
2x^2+5x+11=0
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2x^2 + 5x = -11
2(x^2 + (5/2)x + (5/4)^2 = -11 + 2*(5/4)^2
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2(x+(5/4))^2 = (-176/16)+(50/16)
2(x+(5/4))^2 = (-126/16)
(x+(5/4))^2 = (-63/16)
x+(5/4) = (3/4)sqrt(7)i or x+(5/4) = -(3/4)sqrt(7)i
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x = -(5/4)+(3/4)sqrt(7)i or x = -(5/4)-(3/4)sqrt(7)i
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Cheers,
Stan H.