Two figures are congruent if you can go from one to another through some combination of translations, reflections and rotations. In this tutorial, we'll really internalize this by working through the actual transformations.
Constructing_bisectors_of_lines_angles
With just a compass and a straightedge (or virtual versions of them), you'll be amazed by how many geometric shapes you can construct perfectly. This tutorial gets you started with the building block of how to bisect angle and lines (and how to construct perpendicular bisectors of lines).
Theorems_concerning_quadrilateral_properties
Triangle congruence is not only useful when working with triangles, it's also useful with any other kind of polygon! Prove a few theorems about the properties of parallelograms using triangle congruence.
Learn how to solve different geometric problems using triangle congruence.
Learn how the definition of congruence using rigid transformations can be simplified to simple criteria when studying congruent triangles.
Proofs_of_general_theorems_that_use_triangle_congruence
Gain even more experience with using triangle congruence in proofs.
Theorems_concerning_triangle_properties
Now that we know how to show that two triangles are congruent, let's put that to use by proving some theorems about triangles.
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