Some quadratics cannot be factorised. An alternative method to solve a quadratic equation is to complete the square. To solve an equation of the form \(x^2 + bx + c = 0\) consider the expression ...

{2}\right)^2 = \left(\frac{b}{2}\right)^2 - c\) which can then be solved by taking the square root of both sides. Solve \(x^2 + 6x - 10 = 0\) by completing the square. Halving the value of \(b ...