The Side Between
Part of the Congruence & Proof section of Coddy's Geometry journey. Lesson 22 of 63.
Two angles of a triangle sit at two corners, and exactly one side joins those corners. That side is the included side of the two angles. The other two sides each touch only one of them.
Here the marked angles are at A and B, so the side between them is AB. Its name is made of the two vertices. This is the side version of the included angle from the SAS chapter, and the next rules depend on it.
Challenge
Two angles of triangle LMN are marked with arcs. Tap the side between the two marked angles, then press Check.
Try it yourself
Find the right part on the figure
This lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Congruence & Proof
1What a Proof Is
Given and ProveStatements and ReasonsChaining Equal PartsYour First Full ProofRecap: A Chain of Reasons2Congruent Triangles
Same Size, Same ShapeMatching SidesMatching AnglesWhat Congruence GivesRecap: Matching Parts8Proofs with Vertical Angles
Vertical Angles in ProofsThe BowtieBowtie with ASALinear Pairs in ProofsRecap: Vertical Angles