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

1

1.

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

N.Q.3

G.CO.1

G.CO.8

1

2.

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?

N.Q.3

G.CO.1

G.CO.8

1

3.

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

N.Q.3

G.CO.1

G.CO.8

1

4.

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:

Segment AC coincides with segment ED.

Segment AB coincides with segment EF.

Segment BC coincides with segment DF.

Angle B coincides with angle F.

Angle A coincides with angle E.

N.Q.3

G.CO.1

G.CO.8

1

5.

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.

N.Q.3

G.CO.1

G.CO.8

1

6.

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.

N.Q.3

G.CO.1

G.CO.8

1

7.

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

Triangle FGH is congruent to triangle FEH.

Segment EH is congruent to segment FG.

Segment GH is congruent to segment HE.

Angle HFE is congruent to angle FHG.

Angle EFG is congruent to angle EHG.

Triangle EFH is congruent to triangle GFH.

N.Q.3

G.CO.1

G.CO.8

1

8.

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

Corresponding parts of congruent figures are congruent.

A rectangle has 2 pairs of parallel sides.

Any 2 sides of a rectangle are congruent.

Congruent parts of congruent figures are corresponding.

N.Q.3

G.CO.1

G.CO.8

1

9.

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

N.Q.3

G.CO.1

G.CO.8

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.

IM Algebra 1, Geometry, Algebra 2 is © 2019 Illustrative Mathematics. Licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0).

The Illustrative Mathematics name and logo are not subject to the Creative Commons license and may not be used without the prior and express written consent of Illustrative Mathematics.

These materials include public domain images or openly licensed images that are copyrighted by their respective owners. Openly licensed images remain under the terms of their respective licenses. See the image attribution section for more information.