tan(45°) is 1, so the vertical line above Z must be of length 9 for this to be true. This means WX also has length 9. The line VZ is √(92+92) = 9√2 from Pythagoras. The length of the perimeter is therefore given by:
$${\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{6}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{6}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{2}}}} = {\mathtt{42.727\: \!922\: \!061\: \!357\: \!855\: \!4}}$$
or 42.73 to two decimal places.
tan(45°) is 1, so the vertical line above Z must be of length 9 for this to be true. This means WX also has length 9. The line VZ is √(92+92) = 9√2 from Pythagoras. The length of the perimeter is therefore given by:
$${\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{6}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{6}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{2}}}} = {\mathtt{42.727\: \!922\: \!061\: \!357\: \!855\: \!4}}$$
or 42.73 to two decimal places.