Try showing the circle and axes to emphasise the unit circle origins of the diagram.[br][br]OR[br][br]Hide the circle and axes, and leave two bits of information (side and an angle? two sides?), see if you can calculate the rest.[br]This works best with A in the first quadrant (otherwise the angle will not be an internal angle of the triangle)[br][br]The hypotenuse changes with the slider at the top left.