TeX source:

\begin{array}{l|l|l}x & y=x^{2} & \begin{array}{l}\text { slope of line through } \\ (x, y) \text { and }(2,4)\end{array} \\ \hline 1.5 & 2.25 & 3.5 \\ 1.9 & 3.61 & 3.9 \\ 1.99 & 3.9601 & 3.99 \end{array}