Back to Prove triangles congruent — Problem 3 · Task Set 7

Exercises: Prove Triangles Congruent Using Rigid Motions

Work through each section in order. Show your reasoning where indicated.

Grade 9·20 problems·~35 min·Common Core Math - HS Geometry·standard·hsg-co-b-7

Work through problems with immediate feedback

Fluency Practice

Apply the biconditional and CPCTC directly.

A rigid motion maps $\triangle ABC$ onto $\triangle DEF$ with $A \mapsto D$ , $B \mapsto E$ , $C \mapsto F$ . Which of the following is NOT directly justified by the preservation properties of rigid motions?

$AB = DE$

$\angle B = \angle E$

$\triangle ABC$ and $\triangle DEF$ have the same perimeter

$\angle A + \angle B + \angle C = 180^\circ$ implies $\angle D + \angle E + \angle F = 180^\circ$