Easy listening is a musical style that on the face of it emphasises relaxation and lack of emotional challenge, but at its best can have hidden depths.
... the common denominator is 4a2. We get
<math>\left(x+\frac{b}{2a}\right)^2=\frac{-4ac+b^2}{4a^2}=\frac{b^2-4ac}{4a^2}.</math>
Taking square roots of ...