SOLUTION: solve 2y^2=6y-20 by completing the square

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Question 633166: solve 2y^2=6y-20 by completing the square
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

2y^2=6y-20

2y^2-6y = -20

2(y - 3/2)^2 -9/2  = -20 

2(y - 3/2)^2 =  -31/2

  (y-3/2)^2 = -31/4

     y = 3/2 ± isqrt(31)/2

Checking using Quadratic Formula     

2y^2-6y + 20 = 0

y+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

y+=+%286+%2B-+sqrt%28+-124+%29%29%2F%284%29+

y+=+3%2F2+%2B-+i%2Asqrt%28+31%29%2F2