Lesson 3

Making the Moves

Let's draw and describe translations, rotations, and reflections.

Problem 1

Apply each transformation described to Figure A. If you get stuck, try using tracing paper.

A figure A with a point P, a line l and a point P prime on a triangular grid.
  1. A translation which takes \(P\) to \(P’\)
  2. A counterclockwise rotation of A, using center \(P\), of 60 degrees
  3. A reflection of A across line \(\ell\)

Problem 2

Here is triangle \(ABC\) drawn on a grid.

Triangle A B C on a grid. Let (0 comma 0) be the bottom left corner. Then the coordinates of triangle A B C are A(3 comma 8), B(5 comma 7) and C(8 comma 9).

On the grid, draw a rotation of triangle \(ABC\), a translation of triangle \(ABC\), and a reflection of triangle \(ABC\). Describe clearly how each was done.

Problem 3

Here is quadrilateral \(ABCD\) and line \(\ell\).

Quadrilateral \(A   \)  \(B\)   \(C\)   \(D\) and dashed line \(l\) with a positive slope. \(B\)  \(C\) is parallel to line \(l\). 

Draw the image of quadrilateral \(ABCD\) after reflecting it across line \(\ell\).

(From Unit 1, Lesson 2.)