How do you solve #m^2-4m=3# by completing the square?

1 Answer
Jun 14, 2017

#m=2+-sqrt7#

Explanation:

#"to "color(blue)"complete the square"#

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

#rArr"add " (-4/2)^2=4" to both sides"#

#rArrm^2-4mcolor(red)(+4)=3color(red)(+4)#

#rArr(m-2)^2=7#

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

#sqrt((m-2)^2)=+-sqrt7larr" note plus or minus"#

#rArrm-2=+-sqrt7#

#"add 2 to both sides"#

#rArrm=2+-sqrt7larr" exact values"#