TeX source:
\begin{array}{rclcl} 0 &=& x^2-7x-30 \cr x_{3,4} &=& \dfrac{7}{2} \pm\sqrt{\left(-\dfrac{7}{2}\right)^2+30} \cr &=& \dfrac{7}{2} \pm\sqrt{\dfrac{169}{4}} \cr\cr x_3 &=& \dfrac{7}{2}+\dfrac{13}{2} = 10 & & \rightarrow \quad P_3(10 \mid 5) \cr x_4 &=& \dfrac{7}{2}-\dfrac{13}{2} = -3 & & \rightarrow \quad P_4(-3 \mid 5) \end{array}