SOLUTION: Please show me how solve this quadratic equation by hand, plotting coordinates not needed, thanks so much. -8y^2+2y+7=0

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Question 1021905: Please show me how solve this quadratic equation by hand, plotting coordinates not needed, thanks so much.
-8y^2+2y+7=0
Found 2 solutions by Alan3354, Fombitz:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Please show me how solve this quadratic equation by hand, plotting coordinates not needed, thanks so much.
-8y^2+2y+7=0
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What is "by hand?" I've never solved one using my feet.
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You can complete the square, or use the quadratic equation.
This one cannot be factored, but that's a 3rd method used sometimes.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Complete the square,
-8y%5E2%2B2y%2B7=0
-8%28y%5E2-%281%2F4%29y%29%2B7=0
-8%28y%5E2-%281%2F4%29y%2B1%2F64%29%2B7=-8%2F64
-8%28y-1%2F8%29%5E2=-1%2F8-7
-8%28y-1%2F8%29%5E2=-57%2F8
%28y-1%2F8%29%5E2=57%2F64
y-1%2F8=0+%2B-+sqrt%2857%29%2F8
y=1%2F8+%2B-+sqrt%2857%29%2F8
y=%281+%2B-+sqrt%2857%29%29%2F8