How do you solve using the completing the square method #x^2- 8x + 12 = 0#?

1 Answer
Nov 1, 2017

Answer:

#x=2" or "x=6#

Explanation:

#"place the constant term on the right side"#

#rArrx^2-8x=-12#

#"to use the method of "color(blue)"completing the square"#

#• " ensure the coefficient of the "x^2" term is 1"#

#x^2-8x=-12larrcolor(blue)"coefficient of 1"#

#• " add "(1/2"coefficient of x-term")^2" to both sides"#

#x^2+2(-4)xcolor(red)(+16)=-12color(red)(+16)#

#rArr(x-4)^2=4#

#color(blue)"take the square root of both sides"#

#rArrx-4=+-sqrt4larrcolor(blue)"note plus or minus"#

#rArrx=4+-2#

#rArrx=4+2=6" or "x=4-2=2#