How do you solve using the completing the square method $x^2-4x+2=0$ ?

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Answer 1 · 2017-04-11T12:39:28

$y=(x-2)^2-2$

The completing the square form is:
$y=(x+a)^2+b$

The "a" term will be equal to the middle term divided by two. I.e. $-4/2=-2$ .

This means that you now have the following:

$y=(x-2)^2+b$

Because the completing the square form is equivalent to your original equation you have:

$x^2−4x+2=(x-2)^2+b$
$x^2−4x+2=x^2-4x+4+b$ <-- I expanded the right-hand side
$b=-2$ <--After simplifying you can find the "b"-term

How do you solve using the completing the square method x^2-4x+2=0x^2-4x+2=0?