Unit Vector Polygon Isometries

The quadrilateral ABCD is shown as a square below. Each slider changes different coordinates of the points ABCD: slider a changes x-coordinate of A & C, slider b changes y-coordinate of B & D, slider z changes x-coordinate of B & D and changes y-coordinate of A & C. In this worksheet you will be studying lines of reflection and centers of rotation.

1. Looking at the picture as is, there are 4 lines of reflection. Guess what they are and click on the check boxes to see if you are correct. Do the same for the center of rotation.

2. If you change sliders a, b, and z you will make new quadrilaterals. Write down what kind of quadrilateral you made (as well as the coordinates of A,B,C,D) and say which lines of reflection from the unit square are the same for your new quadrilaterals.

3. Reset the construction and do the line reflections and rotations so that you map ABCD onto itself. Make a table showing how each isometry changes A, B, C and D.

Catherine O'Neill, Created with GeoGebra