Find the equation of the line of reflection. Use the sliders in problem 1 to find this line. Move the problem slider (left top corner of the graph) back to problem 1 to test a theory, then back to problem 2 to see how close you were. When the shape matches positions, you've found the line of reflection and you are officially pretty smart. Don't spend more than 5 minutes on this problem. Check your answer when done.