SOLUTION: Could someone Please show me how to solve this expression I cant seem to get this one. {{{(sqrt2y+7)+4=y}}}

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Could someone Please show me how to solve this expression I cant seem to get this one. {{{(sqrt2y+7)+4=y}}}      Log On


   

Question 98761: Could someone Please show me how to solve this expression I cant seem to get this one.
%28sqrt2y%2B7%29%2B4=y
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(sqrt2y+7)+4=y
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sqrt(2y) = y-11
Square both sides to get:
2y = y^2-22y+121
y^2-24y+121 = 0
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Use the quadratic formula to get:
y = [24 +- sqrt(24^2-4*1*121)]/2
y = [24 +- sqrt(92)]/2
y = [24 +- 2sqrt(23)]/2
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y = [12 + sqrt(23)] or y = [12 - sqrt(23)]
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Cheers,
Stan H.