Reflections
I.SectionObjectives
- Find the reflection of a point in a line on a coordinate plane.
- Multiple matrices.
- Apply matrix multiplication to reflections.
- Verify that a reflection is an isometry.
II.MultipleIntelligences
- To differentiate this lesson, teach the material in the lesson first, and then use this activity to give the students
a hands- on way of practicing multiplying matrix reflections. - Have the students work in pairs.
- They will need graph paper, rulers and colored pencils.
- Students may choose a polygon and draw it on the coordinate grid.
- Then have them show that it is reflected by the liney=x.
- Students take the vertices of their polygon to create a matrix for it.
- Then multiply the matrix of the polygon by the matrix represented byy=x.
- Finally, students show the product in a new matrix.
- Allow time for student sharing in a whole class discussion or in small groups.
- Intelligences- linguistic, logical- mathematical, visual- spatial, interpersonal.
III.SpecialNeeds/Modifications
- Operation with reflections = MULTIPLICATION
- Matrix multiplication-
- Multiply firsts by firsts and seconds by seconds- then add the products
- You can’t multiply a smaller matrix by a larger one.
- You can multiply a larger matrix by a smaller one.
IV.AlternativeAssessment
- Observe students as they work through the assignment.
- Offer assistance when necessary.
- Check for student understanding when discussing the activity in the whole class discussion.
- If students are discussing in small groups, walk around and check in with them.
Rotations
I.SectionObjectives
- Find the image of a point in a rotation in a coordinate plane.
- Recognize that a rotation is an isometry.
- Apply matrix multiplication to rotations.
II.MultipleIntelligences
4.12. Transformations