3: Synthetic Euclidean Geometry Last updated Oct 30, 2021 Save as PDF 2.1: Triangles 3.1: Equivalent Parallel Postulates Page ID89846 Mark A. FitchUniversity of Alaska Anchorage ( \newcommand{\kernel}{\mathrm{null}\,}\) 3.1: Equivalent Parallel Postulates3.2: Similarity3.3: Concurrent3.4: Constructions