C5. The "Semicircle through 2 points" tool
Draw a triangle inscribed in a semicircle
Draw a triangle inscribed in a semicircleAll the triangles inscribed in a semicircle are rectangles if the hypotenuse coincides with the diameter.
1st. Activate the "Semicircle through 2 points" tool 
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2nd. Click on two different points in the Graphics View and you will obtain a semicircle between points "A" and "B".
3rd. Activate the "Move" tool 
and name the semicircle "s".
4th. Activate the "Point" tool 
and click on semicircle "s".
5th. Activate the "Polygon" tool 
and click on the three points "A", "B", "C" and then again on "A" to build an inscribed triangle.
6th. Activate the "Move" tool and name "TR" the triangle.
7th. Activate the "Angle" tool
and click the points "A", "C" and "B". If the angle is different from 90 degrees rectify by erasing the angle first.
8th. Activate the "Move" tool and animate point "C".
The two curved arrows located in the upper right corner of the Graphics View allow you to reset the activity.
If the activity is correct, you will get 10 points automatically.
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2nd. Click on two different points in the Graphics View and you will obtain a semicircle between points "A" and "B".
3rd. Activate the "Move" tool and name the semicircle "s".
4th. Activate the "Point" tool and click on semicircle "s".
5th. Activate the "Polygon" tool and click on the three points "A", "B", "C" and then again on "A" to build an inscribed triangle.
6th. Activate the "Move" tool and name "TR" the triangle.
7th. Activate the "Angle" tool and click the points "A", "C" and "B". If the angle is different from 90 degrees rectify by erasing the angle first.
8th. Activate the "Move" tool and animate point "C".
The two curved arrows located in the upper right corner of the Graphics View allow you to reset the activity.
If the activity is correct, you will get 10 points automatically.