Triangle Area 
Acute triangle (all angles less than 90°) Formula for triangle area (in an acute triangle case) and comparision several variants of that formula.
Made by Antonija Horvatek with the GeoGebra program
For different positions of the slider, investigate ways to find formula of triangle area.
Obtuse triangle (one angle greater than 90°) In the previous applet we found the formula of acute triangle area.
Made by Antonija Horvatek with the GeoGebra program
Use the check boxes and sliders in the given order. Note: If applets don't work correctly, try to use another web browser (Chrome, Mozilla Firefox, Internet Explorer...) or change some properties in the web browser you use. Also, you can try upgrade your web browser.
