Use the slider to change the measure of angle A. Use point B to change the size of the triangle?
What do you notice? What do you wonder?

If you are having trouble with finding questions to ask:
Is there a way to change the triangle, but keep the ratios the same?
What happens when you change the angle? When you move point B?
Why these three ratios?
Can you make a triangle that is the same triangle as a classmates? Can you do it with a different measure of angle A?
Why only these three ratios in the triangle?