Mathematics for IGCSE & O level - Equations (Section 6 - No. 43)
What must be done to the equation x² + 8x + 7 = 0 before completing the square?
Move the constant term to the right side of the equation.
Divide both sides by the coefficient of x² (if it isn't 1).
Isolate the x² and x terms on one side.
Factor out the variable x.
Paliwanag
These steps prepares to add and subtract to complete the square.