Congruent Parts Part 2

​Learning Goal

​Let’s name figures in ways that help us see the corresponding parts.

​Learning Targets

• ​I can identify corresponding parts from a congruence statement.

• I can use rigid transformations to explain why figures are congruent.

• I can write a congruence statement.

​Congruence Statement

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​In the Figure, △ABC is congruent to △DEF. The symbol for congruence is ≅ and we write △ABC≅△DEF. ∠A corresponds to ∠D,  ∠B corresponds to ∠E, and ∠C corresponds to ∠F. Side AB corresponds to DE, BC corresponds to EF, and AC corresponds to DF.

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The Congruence Statement:  △ABC≅△DEF△ABC≅△DEF will always be written so that corresponding vertices appear in the same order, For the triangles in the figure we might also write △BAC≅△EDF, or △ACB≅△DFE but never for example △ABC≅△EDF nor △ACB≅△DEF.

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Therefore, we can always tell which parts correspond just from the congruence statement. For example, given that △ABC≅△DEF, side AB corresponds to side DE because each consists of the first two letters, AC corresponds to DF because each consists of the first and last letters, BC corresponds to EF because each consists of the last two letters.

 

Multiple Choice

Each pair of figures is congruent. Decide whether the congruence statement is true or false.  

• True

• False

Multiple Choice

Each pair of figures is congruent. Decide whether the congruence statement is true or false.  

• True

• False

Multiple Choice

Each pair of figures is congruent. Decide whether the congruence statement is true or false.  

• True

• False

Multiple Choice

Each pair of figures is congruent. Decide whether the congruence statement is true or false.  

• True

• False

Open Ended

Here are three triangles. Triangle PQR is congruent to which triangle? Explain your reasoning.

Open Ended

Describe a sequence of rigid transformations that takes PQR to the triangle you identified as congruent.

Open Ended

Explain why there can’t be a rigid transformation to the other triangle.

Open Ended

Triangle ABD is a rotation of triangle CDB around point E by 180^o. Is angle ADB congruent to angle CDB? If so, explain your reasoning. If not, which angle is ADB congruent to?

Open Ended

Polygon HIJKL is a reflection and translation of polygon GFONM. Is segment KJ congruent to segment NM? If so, explain your reasoning. If not, which segment is NM congruent to?

Open Ended

Quadrilateral PQRS is a rotation of polygon VZYW. Is angle QRS congruent to angle ZYW? If so, explain your reasoning. If not, which angle is QRS congruent to?

​Learning Targets

• ​I can identify corresponding parts from a congruence statement.

• I can use rigid transformations to explain why figures are congruent.

• I can write a congruence statement.

​Complete Exit Ticket in It's Learning