- Understand and prove that the base angles of isosceles trapezoids are congruent.
- Understand and prove that if base angles in a trapezoid are congruent, it is an isosceles trapezoid.
- Understand and prove that the diagonals in an isosceles trapezoid are congruent.
- Understand and prove that if the diagonals in a trapezoid are congruent, the trapezoid is isosceles.
- Identify the median of a trapezoid and use its properties.
II.Cross-curricular-Buildings/Construction
- Use the following image of the Flatiron Building in NYC from Wikipedia.
- This is Figure 06.07.01
- http://www.en.wikipedia.org/wiki/File:Flatiron_crop_20040522_114306_1.jpg
- Print the image so that the students can look at the image in their seats.
- Use this as a feature of discussion.
- Show the students how the sides of the building are the trapezoids.
- This building is formed by three trapezoids and then the top is a triangle.
- Are the students able to identify the type of triangle?
- What would the shape of the building change to if the sides were composed of four trapezoids instead of three?
- You can either have this part as a discussion or as an exploration.
- If you want students to explore this, be sure that they have cardboard, scissors, rulers, tape and a copy of the
image to work with. - Have the student begin by building a rough model of the Flatiron Building as it is now.
- Then they can look at altering it by adding another trapezoid.
- This gives students a discussion point about the building.
- Allow time to discuss and share findings and conclusions following the exploration.
III.TechnologyIntegration
- Ask students to complete a websearch.
- Students are going to google “trapezoid images” for this websearch.
- There will be tons of different images that use trapezoids.
- Ask the students to select five different ones to share.
- If possible, have them print these images, if not they should make notes about the images and where the
trapezoid is in the image. - Also be sure that students write down any websites where the images are located.
- Allow time for students to share their work.
IV.NotesonAssessment
- Assess student understanding of trapezoids through class discussions and sharing.
- Provide students with feedback on their work.
Kites
I.SectionObjectives
- Identify the relationship between diagonals in kites.
- Identify the relationship between opposite angles in kites.
II.Cross-curricular-Kites
3.6. Quadrilaterals