(3+5) to the second power - 2x7
$${\left({\mathtt{3}}{\mathtt{\,\small\textbf+\,}}{\mathtt{5}}\right)}^{{\mathtt{2}}}{\mathtt{\,-\,}}\left({\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{7}}\right) = {\mathtt{50}}$$