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.
At the end, put slider to the 'all' position and compare all given formulas. Do they give the same result?
Also, you can move the vertex of the triangle and check formulas (in acute triangle case).

Obtuse triangle (one angle greater than 90°)

In the previous applet we found the formula of acute triangle area.
In the applet below chech if the same formula is for obtuse triangle.
What about right triangle?

Made by Antonija Horvatek with the GeoGebra program

Use the check boxes and sliders in the given order.
Also, you can move the triangle vertex...

Note:

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