How do you solve using the completing the square method #x^2 + 6x + 7 = 0#?
1 Answer
Mar 31, 2017
Explanation:
To use the method of
#color(blue)"completing the square"#
#• " add ( 1/2 coefficient of x-term")^2# to both sides.
#rArrx^2+6xcolor(red)(+3)^2+7=0color(red)(+3)^2#
#rArrx^2+6x+9=9-7#
#rArr(x+3)^2=2# Take the
#color(blue)"square root of both sides"#
#sqrt((x+3)^2)=+-sqrt2#
#rArrx+3=+-sqrt2#
#rArrx_1=sqrt2-3~~-1.6" to 1 dec. place"#
#rArrx_2=-sqrt2-3~~-4.4" to 1 dec. place"#
