To correct this (completing the square) we need to subtract 19, giving \((x + 3)^2 – 19 = 0\). Rearrange this quadratic to get \((x + 3)^2\) alone on the left-hand side by adding 19 to each side.

The quadratic formula for a quadratic equation ... It is not possible to find the square root of a negative number, so the equation has no real solutions. The graph of \(y = x^2 + 2x + 5\) does ...

A UNSW Sydney mathematician has discovered a new method to tackle algebra's oldest challenge—solving higher polynomial ...