To solve the quadratic by complete square method we proceed as follows: x²-6x+7=0 this can be written as: x²-6x=-7 but c=(-b/2a)^2 c=(-(-6)/2)^2=9 next we add 9 on both sides of our expression to get: x²-6x+9=-7+9 x²-6x+9=2 factoring out the LHS we get: (x-3)(x-3)=2 (x-3)²=2 getting the square root of both sides we obtain: x-3=+/-√2 hence: x=3+/-√2
