SOLUTION: How would I solve y=4x^2-16x-5 by "completing the square?"

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Question 1038234: How would I solve y=4x^2-16x-5 by "completing the square?"
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
How would I solve y=4x^2-16x-5 by "completing the square?"
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y=4x^2-16x-5 = 0
4x^2-16x = 5
x^2-4x = 5/4
Add c. c = (b/2a)^2 = (-4/2)^2 = 4
Add to both sides
x^2-4x+4 = 5/4 + 4 = 21/4
(x-2)^2 = 21/4
x-2 = ħsqrt(21/4) = ħsqrt(21)/2
x+=+2+%2B-sqrt%2821%29%2F2