SOLUTION: how do you solve this? -9=-2x^2+6x

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Question 596611: how do you solve this?
-9=-2x^2+6x
Answer by dhartman0220(8) About Me  (Show Source):
You can put this solution on YOUR website!
-2x^2+6x+9=0
its quadratic so either use the quadratic formula x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
or complete the square....
factor out -2
-2(x^2-3x-9/2)=0
x^2-3x=9/2
add 9/4 to both sides
x^2-3x+9/4=9/2 + 9/4
x^2-3x+9/4=[x-(3/2)]^2
so [x-(3/2)]^2 = 27/4
sqrt both sides x-(3/2) = (+-)sqrt(27/4)
sqrt(27/4)=3sqrt3/2
add 3/2 to both sides.....
x=[3(+-)3sqrt3]/2