Question

solve for completing the square. x squared -8x+12=0. show work please :)

Answer 1

*by

Answer 2

x^2 - 8x +12 = 0
x^2 - 8x = -12
x^2 - 8x +(8/2)^2 = -12 + (8/2)^2
x^2 - 8x + (4)^2 = -12 + (4)^2
x^2 - 8x + 16 = -12 + 16
(x-4)^2 = 4
x-4 = sqrt (4)
x - 4 = +/- 2
x = 4 +/- 2
x = 6
x = 2

Answer 3

x squared -8x +12 = 0
-12 -12
x squared -8x + ____ = -12 + ____

(-8/2)squared
-4squared
16

x squared -8x + 16 = -12 +16

(x-4)squared=4
(x-4)=+/-2
+4 +4
x=4+/- 2
x=6
x=2

Answer 4

Ah! Beat me! ;)

Answer 5

nice game :) you put up a good fight hehe

Answer 6

@ineedhelppleaseee Whenever you need to complete square and you have say
\[x^2+bx+c=0\]
Just add and subtract \(\frac{b^2}{4}\)
We get now
\[x^2+bx+\frac{b^2}{4}-\frac{b^2}{4}+c=0\]
We'll have now

\[(x+\frac{b}{2})^2=\frac{b^2}{4}-c\]
Now you can solve by taking square root both sides
\[(x+\frac{b}{2})=\sqrt{\frac{b^2}{4}-c}\]
so we get
\[x=\sqrt{(\frac{b^2}{4}-c})-\frac{b}{2}\]
Always remember this and you can solve any quadratic

Answer 7

Sorry you'll get in the last step
\[x=\pm\sqrt{(\frac{b^2}{4}-c)}-\frac{b}{2}\]

Answer 8

Hey ash - how do you create the vertical fractions?

Answer 9

See this @TheFigure http://openstudy.com/study#/updates/4f257bb9e4b0a2a9c266f130

Answer 10

and ash just showed you how to derive the quadratic formula :DDD

Answer 11

As long as a=1, yes. :)

Answer 12

Thanks Ash!