Question 102547
x^2-6x-3=0
x^2-6x   =3 add 3 to both sides.
x^2-6x+9=3+9 take -6/2 and square it and add it to both sides making a perfect square on the left.
(x-3)^2=12 factor the left side.
x-3=+-sqrt(12) take sqrt of both sides. 
x-3=+-sqrt(4*3)
x=3+-2sqrt(3)
Ed