Drag points A, B, and C to observe the relationship between angle measurements and side lengths.
Move around each vertex of the triangle. Notice how the triangle and the measurements change. Pay particular attention to the relationship between the angle measures and the side lengths. If you get stuck, there are questions below to guide your discovery. Each question has a textbox for you to record notes and observations. At the bottom make your best guess about how the angle measures and side lengths in a triangle are related.
do all of the angles change?
do all of the side lengths change?
What changes do you notice to the sides and the other angles?
Which side is shortest? Which is longest?
Why do you think that is?
What changes do you notice to the sides and the other angles?
Which side is shortest? Which is longest?
Why do you think that is?
What do you notice about the side length measures?
What do you notice about the other angle and its relationship with the side lengths?
Continue manipulating the triangle in different ways until you see a pattern. Try to determine the pattern that's always true.
What is your best guess at the relationship between angles and sides in a triangle? Do you think that's true for any triangle?