Draw the line of reflection. From a point on the shape, count how far it is vertically from the line of reflection. Count the same amount horizontally on the other side of the line and plot the point.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Hey mathematicians! My name's Ms Szalek and welcome to maths. Today we're going to focus on ...

Materials were written for an entire year's course in geometry in which transformations were used to develop the concepts of congruence, similarity, and symmetry, as well as being a vehicle for proof.