Hello students: this applet is created to illustrate how we can use the pythagorean theorem to tell whether a triangle is acute, right, or straight..

1. Use the slide to adjust the angle to 90 degrees. What do you notice about the areas of the green and blue squares compared to the area of the red square. Because a^2+b^2=c^2, we know we are dealing with a right triangle.
2. Shift the slider so the angle measurement is less than 90 degrees. Notice how the areas change. What can you say about the relationship of c^2 and b^2 + a^2 in an acute triangle?
3. Shift the slider so the angle measurement is more than 90 degrees. Notice how the areas change. What can you say about the relationship of c^2 and b^2 + a^2 in an obtuse triangle?