= Solution
The line passes through $p=(0,1)^T$ and has the same direction as in part (i). Translate by $-p$, reflect by $H$, then translate back. In <homogeneous coordinates> the <affine reflection> is
$$
\boxed{\begin{pmatrix}1&0&0\\0&1&1\\0&0&1\end{pmatrix}\begin{pmatrix}-7/25&24/25&0\\24/25&7/25&0\\0&0&1\end{pmatrix}\begin{pmatrix}1&0&0\\0&1&-1\\0&0&1\end{pmatrix}=\begin{pmatrix}-7/25&24/25&-24/25\\24/25&7/25&18/25\\0&0&1\end{pmatrix}.}
$$
Act on column $(x,y,1)^T$, reading the product from right to left. Every point with $y=4x/3+1$ is fixed. The translation column is $p-Hp$, as for any <reflection in an affine hyperplane>.
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