SOLUTION: Solve for x by completing the square 2x^2+20=4x

Question 685998: Solve for x by completing the square
2x^2+20=4x
Found 2 solutions by stanbon, funmath:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Solve for x by completing the square
2x^2+20=4x
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Divide thru by 2 to get:
x^2 - 2x + 10 = 0
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Complete the square:
x^2 -2x + 1 = -10+1
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(x-1)^2 = -9
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x-1 = +- 3i
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x = 1+3i or x = 1-3i
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Cheers,
Stan H.
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Answer by funmath(2933) (Show Source): You can put this solution on YOUR website!
Solve for x by completing the square

First get the x's together and the constant on the other side.

Then divide the whole equation by any coefficient in front of the x^2...in this case, 2.

At this point, if we call the coefficient of x, b....then we would add (b/2)^2 to both sides.
->

Factor the left and simplify the right. Perfect squares always factor to be the sqrt or the front and back with the sign that is in front of the x term between them...like this.

Take the square root of both sides...don't forget it is always + or -.
=+ or -
If you are only allowed to use "real" solutions...you are done...there is no "real" solution. However, if you are using imaginary or complex numbers...keep going as follows:
x-1= + or -3i
x=1 + or -3i
This is two answers:
or
Happy Calculating!!!!
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