This also gives the equation of the line of symmetry for the quadratic graph ... cross the y-axis at (0, -3). Writing \(y = x^2 - 2x - 3\) in completed square form gives \(y = (x - 1)^2 - 4 ...

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 ...