Completing the square

Solve quadratic equation.
ax2 + bx + c = 0
a=     b=        c=       

      
(x + b/2)2 - (b/2)2 = -c
b/2:    (b/2)2:
(x + b/2)2 = -c+(b/2)2=
x = ±√(-c+(b/2)2) - b/2

Solutions: x1= x2=

Factored: (x-x1)(x-x2) = ax2 + bx + c
(x-)(x-) = x2 +x +

Using x= 

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