since a=1 for ax²+bx²+c=0 we can do take 1/2 of the linear coefient and square it -6/2=-3, (-3)²=9 add that to both sides
x²-3x+9-25=9 factor perfect square trinomial (x-3)²-25=9 add 25 to both sides (x-3)²=34 sqrt both sides, rmember to take positive and negative roots x-3=+/-√34 add 3 x=3+/-√34