HELP I have no idea what any of this is.

In Geometry, "Translation" simply means Moving ... ... without rotating, resizing or anything else, just moving, reflection simply means if x (shape) is in quadrant 4 ( bottom right )and it was reflected across the x axis, it would be in quadrant 3 ( bottom left ), this can change the appearance of some shapes like triangles, a rotation is just a rotation of the shape.

43-73 is not 1 it is -30