How do you solve using the completing the square method #x^2+ 8x + 2 = 0#?
1 Answer
Apr 27, 2017
Explanation:
#"to use the method of "color(blue)"completing the square"# add
#(1/2" coefficient of x-term")^2" to both sides"#
#"that is add " (8/2)^2=16" to both sides"#
#rArr(x^2+8xcolor(red)(+16))+2=0color(red)(+16)#
#rArr(x+4)^2+2=16#
#"subtract 2 from both sides"#
#(x+4)^2cancel(+2)cancel(-2)=16-2#
#rArr(x+4)^2=14#
#color(blue)"take the square root of both sides"#
#sqrt((x+4)^2)=+-sqrt14#
#rArrx+4=+-sqrt14#
#rArrx=-4+-sqrt14#