Complete the square on:

Quote:

Originally Posted by icesta1

Complete the square on:
x^2 - 8x
and
x^2 + 4k

Thanks

You have to add and subtract the square of half of your coefficient of $x$ .

So $x^2 - 8x = x^2 - 8x + (-4)^2 - (-4)^2$

$= \left(x - 4\right)^2 - 16$ .

$x^2 + 4k$ is already complete as the coefficient of $x$ is $0$ .