How can I draw slide with dashed hidden lines

Question

I tried to draw hidden lines as shown in this picture but i could not figure out how to do it. Please help me to fix this problem, I try this code

\begin{document}
\begin{tikzpicture}[z={(3.85mm, -3.85mm)}]
\pgfmathsetmacro{\cubex}{1.5}
\pgfmathsetmacro{\cubey}{1.5}
\pgfmathsetmacro{\cubez}{1.5}
\foreach \x/\j in {0/blue,2.3/blue,4.3/blue} 
\draw[\j] (\x,0,0) -- ++(0,\cubey,0) -- ++(0,0,\cubez) -- ++(0,-\cubey,0) -- cycle;
\end{tikzpicture}

Answer 1

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[z={(3.85mm, -3.85mm)}]
\pgfmathsetmacro{\cubex}{1.5}
\pgfmathsetmacro{\cubey}{1.5}
\pgfmathsetmacro{\cubez}{1.5}
\foreach \x/\j in {0/blue,2.3/blue,4.3/blue} {
\draw[\j] (\x,0,0) -- ++(0,0,\cubez) -- ++(0,-\cubey,0) ;
\draw[dashed,\j] (\x,0,0) -- ++(0,-\cubey,0) -- ++(0,0,\cubez);
}
\end{tikzpicture}
\end{document}