Question

Solve by completing the square. Your answers will involve a, b, or c.

x2+bx+c=0

Answer 1

There is no a in this question. But that's a technicality, I guess...
You know how to complete the square?

Answer 2

or is the question, \(ax^2+bx+c=0\) ??

Answer 3

x^2 + bx +c = 0

x^2 + bx = - c

x^2 + bx + b^2/4 = -c + b^2/4

x^2 + bx + (b/2)^2 = -4c/4 + b^2/4

x^2 + bx + (b/2)^2= (b^2 - 4c) /4

(x + b/2) ^2 = (b^2 - 4c) /4

Take square roots of both sides.

Solve for x.

Don't forget the plus or minus.