Illustrative Mathematics - Geometry - Mathematics - Unit 2 - Lesson 4 - Formative Library | Library

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Match each statement using only the information shown in the pairs of congruent triangles.

Draggable item		Corresponding Item
In the 2 triangles there are 3 pairs of congruent sides.
The 2 sides and the included angle of one triangle are congruent to 2 sides and the included angle of another triangle.
The 2 angles and the included side of one triangle are congruent to 2 angles and the included side of another triangle.

1

Sketch the unique triangles that can be made with angle measures 40° and 100° and side length 3. How do you know you have sketched all possibilities?

1

What is the least amount of information that you need to construct a triangle congruent to this one?

1

Triangle ABC is congruent to triangle EDF. So, Mai knows that there is a sequence of rigid motions that takes ABC to EDF.
Select all true statements after the transformations:

1

A rotation by angle ACE using point C as the center takes triangle CBA onto triangle CDE.
Explain why the image of segment CB lines up with ray CD.
Explain why the image of B coincides with D.
Is triangle ABC congruent to triangle EDC? Explain your reasoning.

1

Line EF is a line of symmetry for figure ABECDF. Clare says that ABEF is congruent to CDFE because sides AB and CD are corresponding.
Why is Clare's congruence statement incorrect?
Write a correct congruence statement for the pentagons.

1

Triangle HEF is the image of triangle HGF after a reflection across line FH. Select all statements that must be true.

1

When rectangle ABCD is reflected across line EF, the image is BADC. How do you know that segment AD is congruent to segment BC?

1

This design began from the construction of a regular hexagon. Describe a rigid motion that will take the figure onto itself.

This lesson is from Illustrative Mathematics. Geometry, Unit 2, Lesson 4. Internet. Available from https://curriculum.illustrativemathematics.org/HS/teachers/2/2/4/index.html ; accessed 29/July/2021.

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Illustrative Mathematics - Geometry - Mathematics - Unit 2 - Lesson 4

Illustrative Mathematics - Geometry - Mathematics - Unit 2 - Lesson 4

Match each statement using only the information shown in the pairs of congruent triangles.

Sketch the unique triangles that can be made with angle measures 40° and 100° and side length 3. How do you know you have sketched all possibilities?

What is the least amount of information that you need to construct a triangle congruent to this one?

Triangle ABC is congruent to triangle EDF. So, Mai knows that there is a sequence of rigid motions that takes ABC to EDF.Select all true statements after the transformations:

A rotation by angle ACE using point C as the center takes triangle CBA onto triangle CDE.Explain why the image of segment CB lines up with ray CD.Explain why the image of B coincides with D.Is triangle ABC congruent to triangle EDC? Explain your reasoning.

Line EF is a line of symmetry for figure ABECDF. Clare says that ABEF is congruent to CDFE because sides AB and CD are corresponding.Why is Clare's congruence statement incorrect?Write a correct congruence statement for the pentagons.

Triangle HEF is the image of triangle HGF after a reflection across line FH. Select all statements that must be true.

When rectangle ABCD is reflected across line EF, the image is BADC. How do you know that segment AD is congruent to segment BC?

This design began from the construction of a regular hexagon. Describe a rigid motion that will take the figure onto itself.

Match each statement using only the information shown in the pairs of congruent triangles.

Sketch the unique triangles that can be made with angle measures 40° and 100° and side length 3. How do you know you have sketched all possibilities?

What is the least amount of information that you need to construct a triangle congruent to this one?

Triangle ABC is congruent to triangle EDF. So, Mai knows that there is a sequence of rigid motions that takes ABC to EDF.Select all true statements after the transformations:

A rotation by angle ACE using point C as the center takes triangle CBA onto triangle CDE.Explain why the image of segment CB lines up with ray CD.Explain why the image of B coincides with D.Is triangle ABC congruent to triangle EDC? Explain your reasoning.

Line EF is a line of symmetry for figure ABECDF. Clare says that ABEF is congruent to CDFE because sides AB and CD are corresponding.Why is Clare's congruence statement incorrect?Write a correct congruence statement for the pentagons.

Triangle HEF is the image of triangle HGF after a reflection across line FH. Select all statements that must be true.

When rectangle ABCD is reflected across line EF, the image is BADC. How do you know that segment AD is congruent to segment BC?

This design began from the construction of a regular hexagon. Describe a rigid motion that will take the figure onto itself.

Triangle ABC is congruent to triangle EDF. So, Mai knows that there is a sequence of rigid motions that takes ABC to EDF.
Select all true statements after the transformations:

A rotation by angle ACE using point C as the center takes triangle CBA onto triangle CDE.
Explain why the image of segment CB lines up with ray CD.
Explain why the image of B coincides with D.
Is triangle ABC congruent to triangle EDC? Explain your reasoning.

Line EF is a line of symmetry for figure ABECDF. Clare says that ABEF is congruent to CDFE because sides AB and CD are corresponding.
Why is Clare's congruence statement incorrect?
Write a correct congruence statement for the pentagons.

Triangle ABC is congruent to triangle EDF. So, Mai knows that there is a sequence of rigid motions that takes ABC to EDF.
Select all true statements after the transformations:

A rotation by angle ACE using point C as the center takes triangle CBA onto triangle CDE.
Explain why the image of segment CB lines up with ray CD.
Explain why the image of B coincides with D.
Is triangle ABC congruent to triangle EDC? Explain your reasoning.

Line EF is a line of symmetry for figure ABECDF. Clare says that ABEF is congruent to CDFE because sides AB and CD are corresponding.
Why is Clare's congruence statement incorrect?
Write a correct congruence statement for the pentagons.