Step 1 : Move the constant number over to the other side
Step 2 : Divide all the terms by a coefficient of x^2.
Step 3 : Take half of the coefficient (dont forget the sign!) of the x-term, and square it. Add this square to both sides of the equation.
Step 4 : Convert the left-hand side to squared form, and simplify the right-hand side.
Step 5 : Solve for x value (Add for x1 and Subtract for x2)