SOLUTION: Solve By completing the square: x^2-4x-2=0 show work

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Question 164188: Solve By completing the square: x^2-4x-2=0 show work
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-4x-2=0
%28x%5E2-4x%29-2=0
Take 1/2 of the x coefficient and square it.
%28-4%2F2%29%5E2=4
Add that to both sides of the equation.
%28x%5E2-4x%2B4%29-2=4
%28x-2%29%5E2=6
%28x-2%29=0+%2B-+sqrt%286%29
x=2+%2B-+sqrt%286%29
or approximately,
x=-.45
x=4.45
.
.
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Check of the solution by graphing the original function.
+graph%28+300%2C+300%2C+-2%2C+6%2C+-5%2C+5%2C+x%5E2-4x-2%29+