Thales's theorem — find the right angle
Thales's theorem — find the right angle
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Which vertex has the right angle (90°)?
Choose the vertex with the right angle.
What does the generator do?
The generator draws a Thales circle with diameter AB and a point C on the semicircle and asks which vertex carries the right angle.
How to solve
Recall Thales's theorem: the angle at the point on a semicircle over the diameter is always 90°. So the right angle is at vertex C.
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