Questions on Algebra: Linear Algebra (NOT Linear Equations) answered by real tutors!

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Question 164188: Solve By completing the square: x^2-4x-2=0 show work: Solve By completing the square: x^2-4x-2=0 show work
Answer by Fombitz(1798) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-4x-2=0
(x^2-4x)-2=0
Take 1/2 of the x coefficient and square it.
(-4/2)^2=4
Add that to both sides of the equation.
(x^2-4x+4)-2=4
(x-2)^2=6
(x-2)=0 +- sqrt(6)
x=2 +- sqrt(6)
or approximately,
x=-.45
x=4.45
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Check of the solution by graphing the original function.
graph( 300, 300, -2, 6, -5, 5, x^2-4x-2)