15.1. Classify Quadrilaterals. Are You Ready? Lesson Opener Making Connections. Resources. Essential Question. Texas Essential Knowledge and Skills

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1 15.1 Classify Quadrilaterals? Essential Question How can you use right angles and parallel sides to help you classify quadrilaterals? How can you use right angles and parallel sides to help you classify quadrilaterals? Lesson Opener Making Connections Invite students to tell you what they know about figures. What figures do you remember learning about? (Triangle,, circle, etc.) What do s, s, es, and s have in common? (They have 4 sides and 4 angles.) Using the Digital Lesson You may wish to have large pictures of a,,, and to use as visual aids when discussing the figures. Learning Task What is the problem the students are trying to solve? Connect the story to the problem. What do you know about the shape of the sign? (It has 4 sides and 4 angles.) Are any of the sides equal in length? (Yes) What are other characteristics about the figure that you notice? (Answers may vary.) Literacy and Mathematics Choose one or more of the following activities. Have students use dot paper to draw 5 to 10 four-sided figures. Have them write about the characteristics that they notice about their figures. Have students draw as many road signs as they can. Have students describe the characteristics of each sign. Texas Essential Knowledge and Skills Geometry and Measurement 3.6.A Classify and sort two- and three-dimensional solids, including cones, cylinders, spheres, triangular and rectangular prisms, and cubes, based on attributes using formal geometric language 3.6.B Use attributes to recognize es, s, s, s, and s as examples of quadrilaterals and draw examples of quadrilaterals that do not belong to any of these subcategories MATHEMATICAL PROCESSES 3.1.D Communicate mathematical ideas and reasoning 3.1.F Analyze mathematical relationships Are You Ready? Access Prior Knowledge Use the Are You Ready? 15.1 in the Assessment Guide to assess students understanding of the prerequisite skills for this lesson. Vocabulary angle, vertex, right angle, parallel lines, quadrilateral,,,,, Go to Multimedia eglossary at thinkcentral.com For the student Resources Interactive Student Edition provides students with an interactive learning environment! Math on the Spot Video Tutor itools Virtual Manipulatives For the teacher Digital Management Center organizes program resources by TEKS! eteacher Edition Online Assessment System Soar to Success Math Online Intervention Lesson A

2 Unlock the Problem This lesson lays the foundation for classifying and measuring angles in later grades. What do we call a plane figure with straight sides that are line segments? a polygon How do you know that two of the angles in Jason s polygon are right angles? You can compare the angles to the corner of a sheet of paper. If you rotate Jason s figure so the corners are both on the bottom or both on the top, are they still right angles? Explain. Yes; possible explanation: changing the position of the angle will not change the type of angle. How would you describe the other angles in Jason s polygon? Possible answer: one angle is greater than a right angle and one angle is less than a right angle. Review with students the meaning of the word parallel. Who can give a real-world example of parallel lines? Possible answer: railroad tracks, steps on a ladder, chains on a swingset Why can t parallel lines ever cross? The lines are always the same distance apart. Why aren t the blue and pink sides of Jason s shape parallel? The lines cross or meet at a right angle. How could you change the shape so there would be 2 pairs of parallel sides? Make the blue side as long as the green side and the orange side as long as the pink side.? 15.1 Classify Quadrilaterals Essential Question Unlock the Problem How can you use right angles and parallel sides to help you classify quadrilaterals? An angle is formed by two rays that share an endpoint. Two dimensional figures have angles formed by two line segments that share an endpoint. The shared endpoint is called a vertex. The plural of vertex is vertices. Jason drew this polygon on dot paper. There are 4 angles. There are 4 sides. Jason s polygon has 2 right angles. They form corners. You can use the corner of a sheet of paper to tell if an angle is a right angle. Draw boxes to show the right angles. Look at Jason s polygon. How many pairs of sides are parallel? Lines that appear to never cross or meet and are always the same distance apart are parallel lines. So, Jason s polygon has 1 pair of parallel sides. Geometry and Measurement 3.6.A, 3.6.B MATHEMATICAL PROCESSES 3.1.D, 3.1.F ray endpoint Math Idea A polygon is a closed plane figure with straight sides that are line segments. Think: Which sides will never cross or meet? Module English Language Learners Leveled Activities Beginning: Activity 20 Intermediate: Activity 25 Advanced: Activity 58 Advanced High: Activity 43 ELPS 1.A.1, 3.G.2, 4.C.3 1.A.2, 3.D.2, 3.H.3, 4.D 2.C.2, 4.C.3, 4.F.9 4.F.8, 4.G.2, 4.G.4 Go to thinkcentral.com for the ELL Activity Guide containing these leveled activities. 481 Module 15 ELL Language Support ELPS 2.C.1, 2.C.2, 2.I.3 Strategy: Explore Context Materials: pairs of things such as shoes, socks, gloves Auditory / Visual Small Group Students use prior knowledge to understand expressions. Explain that a pair is two of something. Point out things that come in pairs: a pair of shoes, a pair of socks, or a pair of gloves. Show two gloves. Here is one pair of gloves. How many gloves are there? 2 Add two more gloves. Here are two pairs of gloves. How many gloves are there now? 4 Show students a and discuss the pairs of parallel sides. Help students see that there are two sides in each pair.

3 Classify Quadrilaterals Quadrilaterals are named by their sides and their angles. Describe quadrilaterals. quadrilateral 4 sides 4 angles ERROR Alert Some quadrilaterals cannot be classified as a,,,, or. Classify Quadrilaterals Discuss with students the meaning of opposite. Ask them to use the word as they would in everyday life. Then discuss the meaning of the word as it pertains to sides of quadrilaterals. exactly 1 pair of opposite sides that are parallel Draw a quadrilateral on the board and indicate opposite sides by drawing arrows that point to each side. Draw an arrow that points to an adjacent side as well. lengths of sides could be the same 2 pairs of opposite sides that are parallel 2 pairs of sides that are of equal length _ 2 pairs of opposite sides that are parallel _ 2 pairs of sides that are of equal length _ 4 right angles _ 2 pairs of opposite sides that are parallel _ 4 sides that are of equal length _ 4 right angles _ 2 pairs of opposite sides that are parallel _ 4 sides that are of equal length Ask students to identify the pair of opposite sides and to explain their choice. Have students make connections to what they have learned about quadrilaterals. What is true about all quadrilaterals? They all have four sides and four angles. How might quadrilaterals be different? Possible answer: they might have different kinds of angles, and not every quadrilateral will have the same number of sides of equal length or the same number of pairs of parallel sides. Have students look at each quadrilateral to complete the descriptions of the quadrilaterals. Then ask: Possible explanation: a is a because it has 2 pairs of opposite sides that are parallel, 2 pairs of sides of equal length, and 4 right angles. A is a because it has 2 pairs of opposite sides that are parallel and 4 sides of equal length. 482 Math Talk Mathematical Processes Explain why a can also be named a or a. Which quadrilaterals have two pairs of opposite sides that are parallel?,,, and Which quadrilaterals are also s? Explain.,, and because opposite sides are parallel and of equal length Are all quadrilaterals also s? Explain. No; possible explanation: a is a quadrilateral, but it is not a. Enrich Visual / Spatial Individual Math Talk Mathematical Processes Use Math Talk to focus on students understanding of why a is a special type of and. Materials: ruler, Dot Paper (see eteacher Resources) Write the following directions on the board and have students draw each shape on dot paper. 1. Draw a quadrilateral with 2 right angles and exactly 1 pair of opposite sides that are parallel. 2. Draw a quadrilateral with 2 pairs of opposite sides that are parallel and 2 angles that are greater than a right angle. Then have students draw another quadrilateral and write directions for how to draw it. Possible directions: Draw a quadrilateral with 4 right angles and all sides of equal length. COMMON ERRORS Error Students may not identify a as a or a. Example Students may not remember the attributes of a or a when identifying possible names for a. Springboard to Learning Review the properties of a, a, and a. Point out that a is a special kind of and a special kind of. Go to Go to thinkcentral.com for additional enrichment activities in the Enrich Activity Guide. Lesson

4 Share and Show The first three problems connect to the learning model. Have students use the MathBoard to explain their thinking. Use the checked exercises for Quick Check IF Quick Check a student misses the checked exercises Share and Show Look at the quadrilateral at the right. 1. How many right angles are in the quadrilateral? 4 right angles 2. Which sides appear to be parallel? a and c, b and d 3. the quadrilateral. Circle all the words that describe the quadrilateral b a d c THEN Differentiate Instruction with RtI Tier 1 Lesson 72 Problem Solving Problems Exercises 6 9 require students to analyze attributes of quadrilaterals. Problem 11 requires students to visualize which quadrilaterals can be named, given the properties listed. Go Deeper To extend students thinking, have students write the name of a quadrilateral and then write a description of it in their own words. Tell them to be sure to write enough information so that if anyone draws it using the description, they will draw the correct figure. Then have volunteers read their descriptions while other volunteers identify the figures. Problem Solving Analyze Write all or some to complete the sentence for The opposite sides of _ all s are parallel. 8. _ Some es are s. 7. _ All sides of a are the same length. 9. _ All s have 1 pair of opposite sides that are parallel. 10. Communicate I am a quadrilateral that has no right angles and 4 sides that are of equal length. What figure am I? 11. Multi-Step I am a polygon that has 4 sides and 4 angles. All of my angles are right angles. Circle all the figures that I could be. quadrilateral Module 15 Lesson Math on the Spot Video Tutor Through the Math on the Spot Video Tutor, students will be guided through an interactive solving of this type of H.O.T. problem. Use this video to also help students solve the H.O.T. problem in the Interactive Student Edition. With these videos and the H.O.T. problems, students will build skills needed in the TEXAS assessment. Math on the Spot videos are in the Interactive Student Edition and at thinkcentral.com RtI Tier 1 Lesson 72 LESSON Classify Quadrilaterals 72 OBJECTIVE Describe, classify, and compare quadrilaterals based on their sides and angles. You can classify quadrilaterals by their sides and by their angles A, 3.6.B 2 pairs of opposite sides that are 2 pairs of opposite sides that are parallel parallel 4 sides that are of equal length 2 pairs of opposite sides that are 4 right angles of equal length 4 right angles 2 pairs of parallel sides 2 pairs of opposite sides that are 2 pairs of equal sides parallel 4 sides that are of equal length 1 pair of opposite sides that are parallel; lengths of sides could be the same How can you classify the quadrilateral? It has only 1 pair of sides that are parallel. The lengths of all 4 sides are not equal. So, the quadrilateral is a. Circle all the words that describe the quadrilateral Enrich 69 Quadrilateral Riddles Read the riddles and name the plane figure that is being described. 1. I am a quadrilateral with exactly 1 pair of opposite sides that are parallel. What shape am I? 3. I am a quadrilateral with 2 pairs of opposite sides that are parallel, 2 pairs of sides that are of equal length, and 4 right angles. I am not a. What shape am I? Enrich I am a quadrilateral with 4 sides that are of equal length and 4 right angles. What shape am I? Possible answers:,, 4. I am a polygon with 4 sides and 4 angles. I do not have any pairs of opposite sides that are parallel. What shape am I? quadrilateral 5. Jerome drew a plane figure and described it as a. Kayla described it as a. Luis described it as a. Can they all be correct? Explain. Yes; possible answer: a is also a because it has 4 sides of equal length. A is also a because it has 2 pairs of opposite sides that are parallel and 2 pairs of sides that are of equal length. 483 Module 15 Geometry and Measurement 143 Enrich E69

5 Daily Assessment Task Fill in the bubble for the correct answer choice. 12. While playing football after school, Jesse notices that the distance marker contains a quadrilateral with one pair of opposite sides that are parallel. What type of quadrilateral is it? A B C D 13. Dean makes a pattern using 10 tiles. How many pairs of opposite sides are parallel in the 10 tiles? A 20 C 40 B 10 D Multi-Step Carina is using scraps of fabric to make a quilt. How many of the fabric scraps are in the shape of es? A 1 C 0 B 2 D 3 Mathematical Processes 2 Daily Assessment Task 1 Can students use right angles and parallel sides to classify quadrilaterals? IF NO YES THEN Soar to Success Math Warm-Up Enrich 69 Homework and Practice Lesson 15.1 TEXAS Test Prep Coach Test Prep Coach helps teachers to identify common errors that students can make. In the Test Prep exercise, if students selected: 3 TEXAS Test Prep 15. What is a true statement about the quadrilateral at the right? 484 A B C D There is 1 right angle. There are 4 right angles. There are no right angles. There are 2 right angles. Image Credits: Photodisc/Getty Images A They do not see the second right angle in the. B They think all 4 angles are right angles in the. C They are unable to identify the 2 right angles in the.? Essential Question Write Math How can you use right angles and parallel sides to help you classify quadrilaterals? All quadrilaterals have 4 sides and 4 angles, and have special names if the opposite sides are parallel or equal in length, or if the angles are right angles. Differentiated Centers Kit Activities Classification Act Students complete orange Activity Card 18 by classifying two-dimensional figures based on their attributes. Activities What Figure? Students complete purple Activity Card 18 by identifying and defining two-dimensional figures by playing a game. Lesson

6 5 Homework and Practice 15.1 Classify Quadrilaterals Circle all the words that describe the quadrilateral Geometry and Measurement 3.6.A, 3.6.B MATHEMATICAL PROCESSES 3.1.D, 3.1.F Lesson Check Fill in the bubble completely to show your answer. 9. Lily makes an art poster that has exactly one pair of opposite sides that are parallel and 2 sides that are the same length. What figure is Lily s poster? A B C D TEXAS Test Prep 10. Desmond draws a polygon that has 4 sides that are the same length and no right angles. How can Desmond classify the polygon he drew? A B C D Problem Solving Write all or some to complete the sentence for Some s are s. 5. Some s have all 4 sides that are equal in length. 7. I am a polygon that has 2 pairs of opposite sides that are parallel. Circle all of the figures that I could be. 4. All angles of a are right angles. 6. Some s have 2 sides that are equal in length. 11. Kara makes the kite shown at the right from 4 triangles. What is the shape of Kara s kite? A B C D quadrilateral quadrilateral 12. Multi-Step Ben is making cutouts to use in an art design. How many of the cutouts have the shape of a? 8. I am a quadrilateral that has 4 right angles. My opposite sides are parallel and of equal length. What figure am I? Module 15 Lesson A 5 B 2 C 4 D 3 Homework and Practice Use the Homework and Practice pages to provide students with more practice on the concepts and skills of this lesson Module 15